Substituted (hetero) aryl compounds, process for their preparation, agents containing them and their use as safeners

ABSTRACT

Substituted (hetero)aryl compounds, process for their preparation, agents containing them, and their use as safeners Compounds of the formula I and their salts, as defined in claim 1, are suitable as safeners for protecting crop plants against the phytotoxic side-effects of herbicides.

This application is a continuation of application Ser. No. 08/099,068,filed Jul. 29, 1993, abandoned.

The invention relates to the technical area of crop-protection agents,in particular active ingredient/antidote combinations, which are highlysuitable for use against competing weeds in crops of useful plants.

Use of crop treatment agents, in particular use of herbicides, canresult in undesired damage to the treated crop plants. Many herbicidesare not fully compatible (selective) with some important crop plants,such as corn, rice or cereals, so that their use is very restricted.They can therefore sometimes not be employed at all or only at such lowapplication rates that the desired broad herbicidal activity against theweeds is not ensured. Thus, for example, many herbicides of thesubstance classes (A) mentioned below cannot be employed sufficientlyselectively in corn, rice or in cereals. In particular in the case ofpost-emergence application of herbicides, phytotoxic side-effects on thecrop plants occur, and it is desired to prevent or reduce thisphytotoxicity.

It has already been disclosed to employ herbicides in combination withcompounds which reduce the phytotoxicity of herbicides in crop plantswithout correspondingly reducing the herbicidal activity against theweeds. Such combination partners are known as "safeners" or "antidotes".

EP-A-31 938 discloses the use of aryloxycarbonitriles andaryloxycarboxamide oximes as safeners for herbicides from the seriesconsisting of the phenoxyphenoxycarboxylic esters, chloroacetanilidesand dimedone derivatives. EP-A-170 906 describes, inter alia,phenoxycarboxylic ester oximes and EP-A-154 153 describes aryloxycompounds as safeners for phenoxyphenoxy and heteroaryloxyphenoxyherbicides.

EP-A-112 799 mentions 4-chlorophenoxy- and4-chloro-2-methylphenoxyacetic acid as safeners for propargyl 2-4-(3,5-dichloropyridyl-2-oxy)phenoxy!propionate.

EP-A-293 062 describes the use of aryloxy compounds as safeners forcyclohexanedione herbicides, and EP-A-88 066 the use of3,5-bis(trifluoromethyl)phenoxycarboxylic acid derivatives as safeners,in particular for acetamides, specifically for triallate.

EP-A-86 750 describesquinoline-8-oxyalkanecarbornitriles andquinoline-8-oxyalkanecarboxamide oximes as safeners forphenoxyphenoxyalkanecarboxylic esters and sulfonyl ureas. EP-A-94 349discloses the use of corresponding carboxylic esters as safeners forherbicides from various structural classes.

DE 2637886 has already disclosed the use of3-pyridyloxyalkanecarboxamides as safeners for herbicides from thetriazine, carbamate and haloacetanilide series.

It has now been found that, surprisingly, a group of aryl and heteroarylderivatives of the formula I below is highly suitable for protectingcrop plants against the harmful effects of aggressive agrochemicals, inparticular herbicides.

Aryl and heteroaryl derivatives which are suitable for protecting cropplants against the harmful effects of aggressive agrochemicals conformto the formula I ##STR1## in which R¹ and R², independently of oneanother, are radicals of the formula ##STR2## in which R, R^(T), R⁴, R⁵,R⁶, Y, T, Z, Q, A_(i), X_(i) and q are as defined below, or

R¹ and R² are bonded to one another and together are a group of theformula

    --CO--Q.sup.1 --D--Q.sup.2 --CO--

in which

Q¹ and Q², independently of one another, are as defined for Q and

D is a divalent group of the formula CR'R" or C═O, where R' and R",independently of one another, are hydrogen or C₁ -C₄ -alkyl,

R³ is hydrogen, halogen, C₁ -C₁₈ -alkyl, C₂ -C₈ -alkenyl, C₂ -C₈-alkynyl, C₁ -C₁₈ -alkoxy, C₂ -C₈ -alkenyloxy, C₂ -C₈ -alkynyloxy, C₁-C₁₈ -alkylthio, C₂ -C₈ -alkenylthio, C₂ -C₈ -alkynylthio, where each ofthe 9 last-mentioned radicals is in each case unsubstituted orsubstituted by one or more radicals from the group consisting ofhalogen, nitro and cyano, or is C₃ -C₁₂ -cycloalkyl which isunsubstituted or substituted by one or more radicals from the groupconsisting of C₁ -C₄ -alkyl, halogen, nitro and cyano, or is SiR^(a)R^(b) R^(c), in which R^(a), R^(b) and R^(c), independently of oneanother, are C₁ -C₄ -alkyl, C₂ -C₄ -alkenyl, C₂ -C₄ -alkynyl orsubstituted or unsubstituted phenyl, or is a radical of the formulaAr'X'--, in which Ar' and X' are defined analogously to Ar and X,

X is O, S, NH--NH or NR^(d), where R^(d) is defined analogously to R⁴,or is --CH₂ O--, --CH₂ S--, --CH(Ar)O-- or --CH(Ar)S--,

Ar is an aromatic radical, for example an unsubstituted or substitutedphenyl, naphthyl or heteroaryl radical, preferably a carbocyclic orcarbobicyclic radical of the formula ##STR3## in which (U) are identicalor different radicals which, independently of one another, are hydrogen,halogen, cyano, nitro, amino or C₁ -C₈ -haloalkyl, C₁ -C₈ -haloalkoxy,C₁ -C₈ -alkyl, C₁ -C₈ -alkoxy, mono-(C₁ -C₄ -alkyl)amino, di-(C₁ -C₄-alkyl)amino, C₁ -C₉ -alkylthio or C₁ -C₈ -alkylsulfonyl, where each ofthe 8 last-mentioned radicals is unsubstituted or substituted by one ormore, preferably up to three identical or different substituents fromthe group consisting of halogen, C₁ -C₈ -haloalkoxy, nitro, cyano,hydroxyl, C₁ -C₈ -alkoxy, in which one or more, preferably up to three,CH₂ groups may be replaced by oxygen, C₁ -C₈ -alkylthio, C₁ -C₆-alkylsulfinyl, C₁ -C₆ -alkylsulfonyl, C₂ -C₈ -alkenylthio, C₂ -C₈-alkynylthio, C₂ -C₈ -alkenyloxy, C₂ -C₈ -alkynyloxy, C₃ -C₇-cycloalkyl, C₃ -C₇ -cycloalkoxy, mono- and di-(C₁ -C₄ -alkyl)amino andC₁ -C₈ -alkoxycarbonyl, and preferably hydrogen, halogen, C₁ -C₆-haloalkyl, such as trifluoromethyl, C₁ -C₆ -haloalkoxy, such asdifluoromethoxy, C₁ -C₆ -alkyl, C₁ -C₆ -alkoxy, C₁ -C₆ -alkylthio, C₁-C₆ -alkylsulfonyl, nitro, amino, (C₁ -C₂ -alkyl)amino, di-(C₁ -C₂-alkyl)amino or cyano, and

o is an integer from 1 to 5, preferably from 1 to 3, and

p is an integer from 1 to 7, preferably from 1 to 3,

or Ar is a monocyclic or bicyclic heteroaryl radical from the groupconsisting of furyl, thienyl, pyrrolyl, pyrazolyl, thiazolyl, oxazolyl,pyridinyl, pyrimidinyl, pyrazinyl, pyridazinyl and guinolinyl, each ofwhich is unsubstituted or substituted by one or more, preferably fromone to three, of said radicals U,

R is hydrogen or an aliphatic, aromatic, heteroaromatic, araliphatic orheteroaraliphatic radical having 1 to 30 carbon atoms and, if desired,containing one or more functional groups, for example R is a hydrogen,C₁ -C₁₈ -alkyl, C₃ -C₁₂ -cycloalkyl, C₂ -C₈ -alkenyl, C₂ -C₈ -alkynyl,heterocyclyl, phenyl or heteroaryl radical,

where each of the above C-containing radicals, independently of oneanother, is unsubstituted or substituted by one or more radicals fromthe group consisting of halogen, cyano, thio, nitro, hydroxyl, C₁ -C₈-alkyl, the latter only in the case of cyclic radicals, C₁ -C₈-haloalkyl, C₁ -C₈ -alkoxy, C₂ -C₈ -alkenyloxy, C₂ -C₈ -alkynyloxy, C₁-C₈ -haloalkoxy, C₁ -C₈ -alkylthio, C₂ -C₈ -alkenylthio, C₂ -C₈-alkynylthio, C₃ -C₇ -cycloalkyl, C₃ -C₇ -cycloalkoxy, radicals of theformulae --NR*R** and --CO--NR*R** and --O--CO--NR*R**, where R* and R**in the three last-mentioned radicals are, independently of one another,hydrogen, C₁ -C₈ -alkyl, C₂ -C₈ -alkenyl, C₂ -C₈ -alkynyl, benzyl,phenyl or substituted phenyl, or together with the nitrogen atom are a3- to 8-membered heterocyclic ring which may contain up to 2 furtherheteroatoms from the group consisting of N, O and S, and may besubstituted by C₁ -C₄ -alkyl, and (C₁ -C₈ -alkoxy)carbonyl, (C₂ -C₈-alkoxy)thiocarbonyl, (C₂ -C₈ -alkenyloxy)carbonyl, (C₁ -C₈-alkylthio)carbonyl,(C₁ -C₈ -alkenylthio)carbonyl, (C₂ -C₈-alkynylthio)carbonyl, (C₂ -C₈ -alkynyloxy)carbonyl, formyl, (C₁ -C₈-alkyl)carbonyl, (C₂ -C₈ -alkenyl)carbonyl, (C₂ -C₈ -alkynyl)carbonyl,C₁ -C₄ -alkylimino, C₁ -C₄ -alkoxyimino, (C₁ -C₈ -alkyl)carbonylamino,(C₂ -C₈ -alkenyl)carbonylamino, (C₂ -C₈ -alkynyl)carbonylamino, (C₁ -C₈-alkoxy)carbonylamino, (C₂ -C₈ -alkenyloxy)carbonylamino, (C₂ -C₈-alkynyloxy)carbonylamino, (C₁ -C₈ -alkyl)aminocarbonylamino, (C₁ -C₆-alkyl)carbonyloxy, which is unsubstituted or substituted by halogen,NO₂, C₁ -C₄ -alkoxy or substituted or unsubstituted phenyl, (C₂ -C₆-alkenyl)carbonyloxy, (C₂ -C₆ -alkynyl)carbonyloxy, (C₁ -C₈alkoxy)carbonyloxy, (C₂ -C₈ alkenyloxy)carbonyloxy,(C₂ -C₈-alkynyloxy)carbonyloxy, C₁ -C₈ -alkylsulfonyl, phenyl, phenyl-C₁ -C₆-alkoxy, phenyl-(C₁ -C₆ -alkoxy)carbonyl, phenoxy, phenoxy-C₁ -C₆-alkoxy, phenoxy-(C₁ -C₆ -alkoxy)carbonyl, phenoxycarbonyl,phenylcarbonyloxy, phenylcarbonylamino, phenyl-(C₁ -C₆-alkyl)carbonylamino and phenyl-(C₁ -C₆ -alkyl)carbonyloxy, where the 11last-mentioned radicals are unsubstituted or substituted on the phenylring by one or more radicals from the group consisting of halogen, C₁-C₄ -alkyl, C₁ -C₄ -alkoxy, C₁ -C₄ -haloalkyl, C₁ -C₄ -haloalkoxy andnitro, and radicals of the formulae --SiR'₃, --O--SiR'₃, (R')₃ Si--C₁-C₆ -alkoxy, --CO--O--NR'₂, --O--N═CR'₂, --N═CR'₂, --O--NR'₂,--CH(OR')₂, and --O--(CH₂)_(m) --CH(OR')₂, in which the R' in saidformulae is, independently of one another, hydrogen, C₁ -C₄ -alkyl orphenyl, which is unsubstituted or monosubstituted or polysubstituted byradicals from the group consisting of halogen, C₁ -C₄ -alkyl, C₁ -C₄-alkoxy, C₁ -C₄ -haloalkyl, C₁ -C₄ -haloalkoxy and nitro, or in pairsare a C₂ -C₆ -alkylene chain and m=0 to 6, or a substituted alkoxyradical of the formula R"O--CHR'"CH(OR")--C₁ -C₆ -alkyl, in which theR", independently of one another, are C₁ -C₄ -alkyl or together are a C₁-C₆ -alkylene group, and R'" is hydrogen or C₁ -C₄ -alkyl,

R^(T) is a radical of the formula --CO--R, --CS--R, --NR^(f) R^(g),--N═CR^(h) R^(i) or SiR^(a) R^(b) R^(c), where R is as defined above,and R^(f), R^(g), R^(h) and R^(i), independently of one another arehydrogen, C₁ -C₄ -alkyl, C₂ -C₄ -alkenyl, C₂ -C₄ -alkynyl, benzyl,phenyl or substituted phenyl, or R^(f) and R^(g) together with thenitrogen atom are a 5- or 6-membered heterocyclic ring which may containup to 2 further heteroatoms from the group consisting of N, O and S, andwhich may be substituted by C₁ -C₄ -alkyl, and R^(a), R^(b) and R^(c),independently of one another, are C₁ -C₄ -alkyl, C₂ -C₄ -alkenyl, C₂ -C₄-alkynyl, phenyl or substituted phenyl,

Y and Z, independently of one another, are oxygen, sulfur in its variousoxidation states, preferably S, SO or SO₂, or --NR^(e), where R^(e) isdefined analogously to R⁴,

R⁴ and R⁵ are identical or different and, independently of one another,are hydrogen, C₁ -C₆ -alkyl, C₂ -C₆ -alkenyl, C₂ -C₆ -alkynyl, (C₁ -C₆-alkyl)carbonyl, where each of the 4 last-mentioned radicals isunsubstituted or substituted by one or more substituents from the groupconsisting of halogen, C₁ -C₈ -haloalkoxy, nitro, cyano, hydroxyl, C₁-C₈ -alkoxy and C₁ -C₈ -alkoxy, in which one or more, preferably up tothree, CH₂ groups which are not bonded directly to one another arereplaced by oxygen, and C₁ -C₈ -alkylthio, C₁ -C₆ -alkylsulfonyl, C₂ -C₈-alkenylthio, C₂ -C₈ -alkynylthio, C₂ -C₈ -alkenyloxy, C₂ -C₈-alkynyloxy, C₃ -C₇ -cycloalkyl, C₃ -C₇ -cycloalkoxy and amino, mono-and di-(C₁ -C₄ -alkyl)amino, or are formyl, SiR^(a) R^(b) R^(c), inwhich R^(a), R^(b) and R^(c), independently of one another, are C₁ -C₄-alkyl, C₂ -C₄ -alkenyl, C₂ -C₄ -alkynyl or substituted or unsubstitutedphenyl, or are C₃ -C₈ -cycloalkyl, C₃ -C₈ -cycloalkenyl, heterocyclylhaving 3 to 7 ring atoms, aryl, heteroaryl or arylcarbonyl, where eachof the 6 last-mentioned radicals is unsubstituted or substituted by oneor more radicals from the group consisting of C₁ -C₈ -alkyl, halogen, C₁-C₈ -haloalkoxy, nitro, cyano, hydroxyl, C₁ -C₈ -alkoxy and C₁ -C₈-alkoxy, in which one or more, preferably up to three, CH₂ groups whichare not bonded directly to one another are replaced by oxygen, and C₁-C₈ -alkylthio, C₁ -C₆ -alkylsulfonyl, C₂ -C₈ -alkenylthio, C₂ -C₈-alkynylthio, C₂ -C₈ -alkenyloxy, C₂ -C₈ -alkynyloxy, C₃ -C₇-cycloalkyl, C₃ -C₇ -cycloalkoxy, and amino, mono- and di-(C₁ -C₄-alkyl)amino, or

R⁴ and R⁵ together are a C₂ -C₄ -alkylene chain or a C₂ -C₄ -alkenylenechain which is unsubstituted or substituted by 1 or 2 radicals from thegroup consisting of methyl, ethyl, methoxy, ethoxy and halogen,

R⁶ is hydrogen, C₁ -C₄ -alkyl, C₂ -C₄ -alkenyl, C₂ -C₄ -alkynyl, C₆ -C₁₂-aryl, heteroaryl, benzyl, C₁ -C₄ -alkoxy, acyloxy, such as (C₁ -C₄-alkyl)carbonyloxy, or unsubstituted or substituted phenylcarbonyloxy,or hydroxyl, --NH--CO--NH₂, --NH--CS--NH₂, mono- and di-(C₁ -C₄-alkyl)amino, --NH-acyl, --NHSO₂ --(C₁ -C₄ -alkyl), C₆ -C₁₂ -aryloxy,heteroaryloxy, NH--SO₂ -aryl, or NH-aryl, in which aryl or heteroaryl inthe 4 last-mentioned radicals is unsubstituted or substituted by one ormore radicals from the group consisting of halogen, nitro, (C₁-C₄)-alkyl, (C₁ -C₄)-alkoxy, (C₁ -C₄)-haloalkyl and (C₁ -C₄)-haloalkoxy,

T is O, S, NR⁷, NOR⁷ or NO-acyl,

Q is O or S,

q is a integer from 0 to 4,

i is a serial number which, if q is not equal to 0, adopts all integersfrom 1 to q, where q is as defined above,

X_(i) independently of one another, are O, S, NR⁷ or N--(A_(i)--X_(i))_(q) --R,

A_(i) independently of one another, are unsubstituted or substituted C₁-C₆ -alkylene, C₂ -C₆ -alkenylene, C₂ -C₆ -alkynylene, C₃ -C₆-cycloalkylene, C₃ -C₆ -cycloalkenylene, heterocyclylene, arylene orheteroarylene, and

R⁷ independently of one another, are H, C₁ -C₄ -alkyl, C₂ -C₄ -alkenyl,C₂ -C₄ -alkynyl, C₃ -C₆ -cycloalkyl, C₃ -C₆ -cycloalkenyl, heterocyclyl,aryl or heteroaryl.

In the formula (I) and below, the alkyl, alkoxy, haloalkyl, haloalkoxy,alkylamino and alkylthio radicals and the corresponding unsaturatedand/or substituted radicals in the carbon skeleton are eachstraight-chain or branched. Unless specifically stated, these radicalsin which the carbon skeletons have 1 to 4 carbon atoms or in the case ofunsaturated groups have 2 to 4 carbon atoms are preferred. Alkylradicals, also in combination meanings such as alkoxy, haloalkyl, etc.,are, for example, methyl, ethyl, n- or i-propyl, n-, i-, t- or 2-butyl,pentyls, hexyls, such as n-hexyl, i-hexyl and 1,3-dimethylbutyl,heptyls, such as n-heptyl, 1-methylhexyl and 1,4-dimethylpentyl; alkenyland alkynyl radicals have the meaning of the possible unsaturatedradicals corresponding to the alkyl radicals, alkenyl is, for example,allyl, 1-methylprop-2-en-1-yl, 2-methylprop-2-en-1-yl, but-2-en-1-yl,but-3-en-1-yl, 1-methyl-but-3-en-1-yl and 1-methyl-but-2-en-1-yl;alkynyl is, for example, propargyl, but-2-yn-1-yl, but-3-yn-1-yl,1-methyl-but-3-yn-1-yl. Halogen is fluorine, chlorine, bromine oriodine, preferably fluorine, chlorine or bromine, in particular fluorineor chlorine. Haloalkyl, -alkenyl and -alkynyl are partially or fullyhalogen-substituted alkyl, alkenyl and alkynyl respectively, forexample, CF₃, CHF₂, CH₂ F, CF₃ CF₂, CH₂ FCHCl, CCl₃, CHCl₂ or CH₂ CH₂Cl; haloalkoxy is, for example, OCF₃, OCHF₃, OCH₂ F, CF₃ CF₃ O or OCH₂CF₃. The corresponding applies to haloalkenyl and otherhalogen-substituted radicals.

Aryl is, for example, phenyl, naphthyl, tetrahydronaphthyl, indenyl,indanyl, pentalenyl, fluorenyl and the like, preferably phenyl; aryloxyis preferably the oxy radicals corresponding to said aryl radicals, inparticular phenoxy.

Heteroaryl and heteroaryl in heteroaryloxy are, for example, pyridyl,pyrimidinyl, pyridazinyl, pyrazinyl, thienyl, thiazolyl, oxazolyl,furyl, pyrrolyl, pyrazolyl and imidazolyl, but also bicyclic orpolycyclic aromatic or araliphatic compounds, for example quinolinyl,benzoxazolyl, etc.

Substituted aryl or aryloxy, heteroaryl, heteroaryloxy, phenyl, phenoxy,benzyl, benzyloxy and substituted bicyclic radicals containing aromaticmoieties are, for example, a substituted radical derived from theunsubstituted parent structure, where the substituents are, for example,one or more, preferably 1, 2 or 3, radicals from the group consisting ofhalogen, alkyl, haloalkyl, alkoxy, haloalkoxy, hydroxyl, amino, nitro,cyano, alkoxycarbonyl, alkylcarbonyl, formyl, carbamoyl, mono- anddialkylaminocarbonyl, mono- and dialkylamino, alkylsulfinyl andalkylsulfonyl, and in the case of radicals containing carbon atoms thosehaving 1 to 4 carbon atoms, in particular 1 or 2 carbon atoms, arepreferred.

Preference is generally given to substituents from the halogen group,for example fluorine and chlorine, C₁ -C₄ -alkyl, preferably methyl orethyl, C₁ -C₄ -haloalkyl, preferably trifluoromethyl, C₁ -C₄ -alkoxy,preferably methoxy or ethoxy, C₁ -C₄ -haloalkoxy, nitro and cyano.Particular preference is given to the substituents methyl, methoxy andchlorine.

Substituted or unsubstituted phenyl is, for example, phenyl which isunsubstituted or monosubstituted or polysubstituted, preferably up totrisubstituted, by identical or different radicals from the groupconsisting of halogen, (C₁ -C₄)-alkyl, (C₁ -C₄)-alkoxy, (C₁-C₄)-haloalkyl, (C₁ -C₄)-haloalkoxy and nitro, for example o-, m- andp-tolyl, dimethylphenyl, 2-, 3- and 4-chlorophenyl, 2-, 3- and4-trifluoro- and -trichlorophenyl, 2,4-, 3,5-, 2,5- and2,3-dichlorophenyl, and o-, m- and p-methoxyphenyl.

A three- to seven-membered heterocyclic radical as described above ispreferably derived from benzene, in which at least one CH has beenreplaced by N and/or at least two adjacent CH pairs have been replacedby NH, S and/or O. The radical may be benzo-fused. If desired, it can bepartially or fully hydrogenated, and is then also known as heterocyclyl.Particularly suitable radicals are those such as oxiranyl, pyrrolidyl,piperidyl, dioxolanyl, pyrazolyl, morpholyl, furyl, tetrahydrofuryl,indolyl, quinolinyl, pyrimidyl, azepinyl, triazolyl, thienyl andoxazolyl.

Acyl is, for example, formyl, alkylcarbonyl, such as (C₁ -C₄-alkyl)carbonyl, phenylcarbonyl, in which the phenyl ring may besubstituted, for example as shown above for phenyl, or alkoxycarbonyl,phenoxycarbonyl, benzyloxycarbonyl, alkylsulfonyl and other radicals oforganic acids.

Some compounds of the formula I contain one or more asymmetric carbonatoms or double bonds, which are not indicated separately in the formulaI. The possible stereoisomers defined by their specific spatial shape,such as enantiomers, diastereomers, E- and Z-isomers, and mixturesthereof, are, however, all covered by the formula I.

The compounds of the formula I which are derived from carboxylic acidscan form salts in which the radical R is replaced by an equivalent of acation which is suitable for agriculture. These salts are, for example,metal salts, in particular alkali metal or alkaline earth metal salts,but also ammonium salts or salts with organic amines, and salts whichcontain sulfonium or phosphonium ions as cations.

Suitable salt formers are, in particular, metals and organic nitrogenbases, especially quaternary ammonium bases. Metals which are suitablehere for salt formation are alkaline earth metals, such as magnesium orcalcium, but especially alkali metals, such as lithium and in particularpotassium and sodium.

Examples of nitrogen bases which are suitable for salt formation areprimary, secondary or tertiary aliphatic and aromatic amines, which maybe hydroxylated on the hydrocarbon radical, such as methylamine,ethylamine, propylamine, isopropylamine, the four isomeric butylamines,dimethylamine, diethylamine, dipropylamine, diisopropylamine,di-N-butylamine, pyrrolidine, piperidine, morpholine, trimethylamine,triethylamine, tripropylamine, quinuclidine, pyridine, quinoline,isoquinoline and methanolamine, ethanolamine, propanolamine,dimethanolamine, diethanolamine or triethanolamine.

Examples of quaternary ammonium bases are tetraalkylammonium cations inwhich the alkyl radicals, independently of one another, arestraight-chain or branched C₁ -C₆ -alkyl groups, such as thetetramethylammonium cation, the tetraethylammonium cation or thetrimethylethylammonium cation, and furthermore thetrimethylbenzylammonium cation, the triethylbenzylammonium cation andthe trimethyl-2-hydroxyethylammonium cation.

Particularly preferred salt formers are the ammonium cation and di- andtrialkylammoniumcations in which the alkyl radicals, independently ofone another, are straight-chain or branched, unsubstituted orhydroxyl-substituted (C₁ -C₆)-alkyl groups, such as, for example, thedimethylammonium cation, the trimethylammonium cation, thetriethylammonium cation, the di-(2-hydroxyethyl)ammonium cation and thetri-(2-hydroxyethyl)ammonium cation.

Of particular interest are compounds of the formula (I), or saltsthereof, in which

R³ is hydrogen, C₁ -C₄ -alkyl, C₁ -C₄ -alkoxy, C₅ -C₆ -cycloalkyl,trimethylsilyl, triethylsilyl or a radical of the formula Ar'X'--, inwhich Ar' and X' are defined analogously to Ar and X respectively,

X is O, S, NH, NCH₃ or NC₂ H₅,

Ar is a radical of the formula ##STR4## in which (U) are identical ordifferent radicals which, independently of one another, are hydrogen,halogen, such as fluorine, chlorine, bromine and iodine, cyano, nitro,amino or C₁ -C₄ -haloalkyl, C₁ -C₄ -haloalkoxy, C₁ -C₄ -alkyl, C₁ -C₄-alkoxy, mono-(C₁ -C₄ -alkyl)amino, di-(C₁ -C₄ -alkyl)amino, C₁ -C₄-alkylthio or C₁ -C₄ -alkylsulfonyl, and

o is an integer from 1 to 3, and

p is an integer from 1 to 3, or

Ar is a monocyclic or bicyclic heteroaryl radical from the groupconsisting of furyl, thienyl, pyrrolyl, pyrazolyl, thiazolyl, oxazolyl,pyridinyl, pyrimidinyl, pyrazinyl, pyridazinyl and quinolinyl, which isunsubstituted or substituted by one to three of the abovementionedradicals U.

Of particular interest are also compounds of said formula (I) and saltsthereof in which

R is hydrogen, C₁ -C₈ -alkyl, C₄ -C₇ -cycloalkyl, C₂ -C₈ -alkenyl, C₂-C₈ -alkynyl, heterocyclyl, phenyl or heteroaryl,

where each of the 7 last-mentioned radicals, independently of oneanother, is unsubstituted or substituted by one or more radicals fromthe group consisting of halogen, cyano, thio, nitro, hydroxyl, C₁ -C₄-alkyl, the latter only in the case of cyclic radicals, C₁ -C₄-haloalkyl, C₁ -C₄ -alkoxy, C₂ -C₄ -alkenyloxy, C₂ -C₄ -alkynyloxy, C₁-C₄ -haloalkoxy, C₁ -C₄ -alkylthio, C₂ -C₄ -alkenylthio, C₂ -C₄-alkynylthio, C₅ -C₆ -cycloalkyl, C₅ -C₆ -cycloalkoxy, amino, mono- anddi-(C₁ -C₄ -alkyl)amino, (C₁ -C₆ -alkoxy)carbonyl, radicals of theformulae --SiR'₃, --O--NR'₂, --O--N═CR'₂, --N═CR'₂, in which the R' insaid formulae are, independently of one another, hydrogen, C₁ -C₂ -alkylor phenyl or in pairs are a C₂ -C₅ -alkylene chain, or

compounds in which

R^(T) is a radical of the formula --CO--R, --NR^(f) R^(g) or --N═CR^(h)R^(i), where R, R^(f), R^(g), R^(h) and R^(i) are as defined above.

R is preferably hydrogen, C₁ -C₈ -alkyl, C₅ -C₆ -cycloalkyl, C₂ -C₈-alkenyl or C₂ -C₈ -alkynyl, where each of the 4 last-mentionedradicals, independently of one another, are unsubstituted or substitutedby one or more radicals from the group consisting of halogen, cyano,nitro, C₁ -C₄ -alkoxy, C₂ -C₄ -alkenyloxy, C₂ -C₄ -alkynyloxy, C₅ -C₆-cycloalkyl, C₅ -C₆ -cycloalkoxy, mono- and di-(C₁ -C₄ -alkyl)amino,radicals of the formulae --SiR'₃, --O--N═CR'₂, --N═CR'₂, in which the R'in said formulae are, independently of one another, hydrogen, C₁ -C₂-alkyl or phenyl or in pairs are a C₂ -C₅ -alkylene chain.

R^(T) is preferably --CO--R, where R is as defined above, or --NR^(f)R^(g) or --N═CR^(h) R^(i), in which

R^(f) and R^(g), independently of one another, are H, C₁ -C₂ -alkyl,benzyl or phenyl or together with the nitrogen atom are pyrrolidin-1-yl,piperidin-1-yl, morpholin-4-yl, piperazin-1-yl or imidazol-1-yl, and

R^(h) and R^(i), independently of one another, are H, C₁ -C₂ -alkyl,benzyl or phenyl.

Of particular interest are also compounds of said formula (I) and saltsthereof, in which

R⁴ and R⁵ are identical or different and, independently of one another,are hydrogen, C₁ -C₄ -alkyl, C₂ -C₄ -alkenyl, C₂ -C₄ -alkynyl, C₅ -C₆-cycloalkyl or C₅ -C₆ -cycloalkenyl,

and compounds in which

R⁶ is hydrogen, C₁ -C₄ -alkyl, phenyl, benzyl, hydroxyl, NH--CO--NH₂,--NH-aryl or C₁ -C₄ -alkoxy.

Of particular interest are also compounds of the said formula (I) andsalts thereof, in which

T is O, S or NR⁷, preferably O or NR⁷,

Q is O or S, preferably O,

q is an integer from 0 to 4,

i is a serial number which, if q is not equal to 0, adopts all integersfrom 1 to q, where q is as defined above,

X_(i) independently of one another, are O, S, NR⁷ or N--(A_(i--X)_(i--))_(q) --R,

A_(i) independently of one another, are unsubstituted, or substituted C₁-C₄ -alkylene, C₂ -C₄ -alkenylene or C₅ -C₆ -cycloalkylene, preferablyC₁ -C₄ -alkylene,

R⁷ independently of one another, are H, C₁ -C₄ -alkyl, C₂ -C₄ -alkenyl,C₂ -C₄ -alkynyl or C₅ -C₆ -cycloalkyl.

Preference is given to compounds of the formula (I), and salts thereof,in which

R¹ and R², independently of one another, are radicals of the formula##STR5## or CN in which R, T, Q, A_(i), X_(i) and q are as definedabove.

The invention also relates to a process for protecting crop plants,preferably cereal, rice or corn plants, against phytotoxic side-effectsof herbicides, which comprises applying an effective amount of at leastone compound of the formula I, or a salt thereof, to the plants, plantseeds or cultivated area before, after or simultaneously with theabovementioned herbicidal active compound.

The invention furthermore relates to the use of compounds of the formulaI, or salts thereof, for protecting crop plants against phytotoxicside-effects of herbicides.

Some of the compounds of the formula I are known, such as, for example,diethyl 2-(quinoline-8-yl-mercapto)malonate and ethyl2-(quinoline-8-mercapto)acetoacetate (G. Buchmann, J. prakt. Chem. 1965,141); diethyl 4-chlorophenoxymalonate (J. Izv. Sibirsk. Ord. Akad. Nauk.SSSR 1962 (11), 145-8, see Chem. Abstracts 59:5051 g (1963)). However,their safener action had hitherto not been disclosed.

The invention also relates to all compounds of the formula I which hadnot been disclosed hitherto.

The compounds of the formula I can be prepared by processes which areknown in general terms; see, for example, EP-A-4433; J. Am. Chem. Soc.62 (1990) 1154; J. Org. Chem. 36 (1971) 3646; Chem. Abstr. 111 (1988)133625 q; EP-A-326328; J. Am. Chem. Soc. 94 (1972) 712; Ukr. Khim. Zh.(Russ. Ed.) 56 (1990) 638; Chem. Abstr. 114 (1991) 42155 g; Chem. Pharm.Bull. 17 (1969) 419; Chem. Lett. 1973, 287; J. Chem. Soc. Chem. Comm.1979, 50; Bull. Chem. Soc. Jpn. 45 (1972) 866; J. Org. Chem. 39 (1974)1233 and the references cited therein.

Thus, the compounds of the formula I according to the invention can beprepared by

a) reacting a compound of the formula Ar--X--H, in which Ar and X are asdefined under formula I, with a compound of the formula II ##STR6## inwhich L is a leaving group, such as, for example, chlorine, bromine,methanesulfonyl or toluenesulfonyl, and

R¹, R² and R³ are as defined under said formula I, or

b) reacting a compound of the formula Ar--W with a compound of theformula III ##STR7## where W is a leaving group, such as, for example,chlorine, bromine, methanesulfonyl or toluenesulfonyl, and

Ar, X, R¹, R² and R³ are as defined under said formula I, or

c) reacting a compound of the formula AR--X--W with a compound of theformula IV ##STR8## where W is a leaving group, such as, for example,chlorine, methanesulfonyl, toluenesulfonyl, dialkylamino, diacylamino orarylthio, and

Ar, X, R¹, R² and R³ are as defined under formula I, or

d) transesterifying an aryl- or heteroaryloxycarboxylic acid derivativeof the formula V ##STR9## in which Ar, X, R¹ and R³ are as defined underformula I, and B' is a group of the formula ##STR10## or R¹ and B¹ arebonded to one another and together are a group of the formula --CO--Q¹--D--Q² --CO--, where T, Q, A_(i), X_(i), q, R, R^(T) Q¹, Q² and D aredefined analogously to the radicals of the same names in formula I, withalcohols or mercaptans.

The reactions in variant a) are preferably carried out in dipolaraprotic solvents, such as dimethyl sulfoxide, N,N-dimethylformamide,methyl isobutyl ketone, dioxane or acetone, at elevated temperature, inparticular at between 40° and 180° C., in the presence of a base, inparticular alkali metal carbonates, such as, for example, potassiumcarbonate.

The reactions in variant b) are preferably carried out in aproticsolvents, such as toluene, N,N-dimethylformamide, acetonitrile, methylisobutyl ketone, dioxane or acetone, at elevated temperature, inparticular at between 40° and 180° C., in the presence of a base, inparticular alkali metal carbonates, such as, for example, potassiumcarbonate.

The reactions in variant c) are preferably carried out in aproticsolvents, such as dimethyl sulfoxide, N,N-dimethylformamide,tetrahydrofuran, dioxane or methylene chloride, or in alcohols, such asmethanol, ethanol, at from room temperature to elevated temperature, inparticular at between 20° and 100° C., in the presence of a base, inparticular alkali metal alkoxides, such as, for example, sodiummethoxide or sodium ethoxide.

The transesterifications or amidations in variant d) are principallycarried out by reacting a compound of the formula V with the alcohols orthe amines at elevated temperatures, in particular at the refluxtemperature of the reaction mixture, in the presence of titaniumalkoxides as catalyst.

Compounds of the formula I reduce or suppress phytotoxic side-effects ofherbicides which can occur when the herbicides are used in crops ofuseful plants, and can therefore be referred to in the usual manner asantidotes or safeners.

The compounds of the formula I according to the invention can be appliedtogether with herbicidal active compounds or in any desired sequence andare then capable of reducing or fully eliminating harmful side-effectsof these herbicides in crop plants without impairing the effectivenessof these herbicides against weeds.

This allows the area of application of conventional crop-protectionagents to be very substantially broadened. Herbicides whose phytotoxicside-effects on crop plants can be reduced by means of compounds of theformula I are, for example, carbamates, thiocarbamates,haloacetanilides, substituted phenoxy-, naphthoxy- andphenoxyphenoxycarboxylic acid derivatives andheteroaryloxyphenoxyalkanecarboxylic acid derivatives, such asquinolyloxy-, quinoxalyloxy-, pyridyloxy-, benzoxalyloxy- andbenzothiazolyloxyphenoxyalkanecarboxylic esters, cyclohexanedionederivatives, imidazolinones, pyrimidyloxypyridinecarboxylic acidderivatives, pyrimidyloxybenzoic acid derivatives, sulfonylureas,triazolopyrimidinesulfonamide derivatives andS-(N-aryl-N-alkylcarbamoylmethyl)dithiophosphonic esters. Preference isgiven to phenoxyphenoxy- and heteroaryloxyphenoxycarboxylic esters andsalts, sulfonylureas and imidazolinones.

Suitable herbicides which can be combined with the safeners according tothe invention are, for example:

A) Herbicides of the (C₁ -C₄)-alkyl, (C₂ -C₄)alkenyl and (C₃ -C₄)alkynylphenoxyphenoxy- and heteroaryloxyphenoxycarboxylate, such as

A1) Phenoxyphenoxy- and benzyloxyphenoxycarboxylic acid derivatives, forexample

methyl 2-(4-(2,4-dichlorophenoxy)phenoxy)propionate (diclofop-methyl),

methyl 2-(4-(4-bromo-2-chlorophenoxy)phenoxy)propionate (seeDE-A-2601548),

methyl 2-(4-(4-bromo-2-fluorophenoxy)phenoxy)propionate (see U.S. Pat.No. 4,808,750),

methyl 2-(4-(2-chloro-4-trifluoromethylphenoxy)phenoxy)propionate (seeDE-A-2433067),

methyl 2-(4-(2-fluoro-4-trifluoromethylphenoxy)phenoxy)propionate (seeU.S. Pat. No 4,808,750),

methyl 2-(4-(2,4-dichlorobenzyl)phenoxy)propionate (see DE-A-2417487),

ethyl 4-(4-(4-trifluoromethylphenoxy)phenoxy)pent-2-enoate,

methyl 2-(4-(4-trifluoromethylphenoxy)phenoxy)propionate (seeDE-A-2433067),

A2) "Monocyclic" heteroaryloxyphenoxyalkanecarboxylic acid derivatives,for example,

ethyl 2-(4-(3,5-dichloropyridyl-2-oxy)phenoxy)propionate (seeEP-A-2925),

propargyl 2-(4-(3,5-dichloropyridyl-2-oxy)phenoxy)propionate (seeEP-A-3114),

methyl 2-(4-(3-chloro-5-trifluoromethyl-2-pyridyloxy)phenoxypropionate(see EP-A-3890),

ethyl 2-(4-(3-chloro-5-trifluoromethyl-2-pyridyloxy)phenoxy)propionate(see EP-A-3890),

propargyl 2-(4-(5-chloro-3-fluoro-2-pyridyloxy)phenoxy)propionate(EP-A-191736),

butyl 2-(4-(5-trifluoromethyl-2-pyridyloxy)phenoxy)propionate(fluazifop-butyl),

A3) "Bicyclic" heteroaryloxyphenoxyalkanecarboxylic acid derivatives,for example

methyl and ethyl 2-(4-(6-chloro-2-quinoxalyloxy)phenoxy)propionate(quizalofop-methyl and -ethyl),

methyl 2-(4-(6-fluoro-2-quinoxalyloxy)phenoxy)propionate (see J. Pest.Sci. Vol. 10, 61 (1985)),

2-(4-(6-chloro-2-quinoxalyloxy)phenoxy)propionic acid and the2-isopropylideneaminooxyethyl ester thereof (propaquizafop and ester),

ethyl 2-(4-(6-chlorobenzoxazol-2-yl-oxy)phenoxy)propionate(Fenoxaprop-ethyl), and the D(+) isomer thereof (Fenoxaprop-P-ethyl),

ethyl 2-(4-(6-chlorobenzothiazol-2-yloxy)phenoxypropionate (seeDE-A-2640730),

tetrahydrofur-2-yl-methyl 2-(4-(6-chloroquinoxalyloxy)phenoxypropionate(see EP-A-323 727),

B) Herbicides from the sulfonylurea series, such as, for example,pyrimidine- or triazinylaminocarbonyl- benzene, pyridine, pyrazole,thiophene, and (alkylsulfonyl)alkylamino!sulfamides. Preferredsubstituents on the pyrimidine ring or triazine ring are alkoxy, alkyl,haloalkoxy, haloalkyl, halogen or dimethylamino, where all thesubstituents can be combined, independently of one another. Preferredsubstituents in the benzene, pyridine, pyrazole, thiophene or(alkylsulfonyl)alkylamino moiety are alkyl, alkoxy, halogen, nitro,alkoxycarbonyl, aminocarbonyl, alkylaminocarbonyl, dialkylaminocarbonyl,alkoxyaminocarbonyl, alkyl, alkoxyaminocarbonyl, haloalkoxy, haloalkyl,alkylcarbonyl, alkoxyalkyl, and (alkanesulfonyl)alkylamino. Suitablesulfonylureas are, for example,

B1) Phenyl- and benzylsulfonylureas and related compounds, for example,

1-(2-chlorophenylsulfonyl)-3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)urea(chlorsulfuron),

1-(2-ethoxycarbonylphenylsulfonyl)-3-(4-chloro6-methoxypyrimidine-2-yl)urea(chlorimuron-ethyl),

1-(2-methoxyphenylsulfonyl)-3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)urea(metsulfuron-methyl),

1-(2-chloroethoxyphenylsulfonyl)-3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)urea(triasulfuron),

1-(2-methoxycarbonylphenylsulfonyl)-3-(4,6-dimethylpyrimidin-2-yl)urea(sulfometuron-methyl),

1-(2-methoxycarbonylphenylsulfonyl)-3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)-3-methylurea(tribenuronmethyl),

1-(2-methoxycarbonylbenzylsulfonyl)-3-(4,6-dimethoxypyrimidin-2-yl)urea(bensulfuron-methyl),

1-(2-methoxycarbonylphenylsulfonyl)-3-(4,6-bis(difluoromethoxy)pyrimidin-2-yl)urea(primisulfuron-methyl,

3-(4-ethyl-6-methoxy-1,3,5-triazin-2-yl)-1-(2,3-dihydro-1,1-dioxo-2-methylbenzob!thiophene-7-sulfonyl)urea (see EP-A-79683),

3-(4-ethoxy-6-ethyl-1,3,5-triazin-2-yl)-1-(2,3-dihydro-1,1-dioxo-2-methylbenzob!thiophene-7-sulfonyl)urea (see EP-A-79683),

B2) Thienylsulfonylureas, for example1-(2-methoxy-carbonylthiophen-3-yl)-3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)urea(thifensulfuron-methyl),

B3) Pyrazolylsulfonylureas, for example

1-(4-ethoxycarbonyl-1-methylpyrazol-5-ylsulfonyl)-3-(4,6-dimethoxypyrimidin-2-yl)urea(pyrazosulfuron-methyl),

methyl3-chloro-5-(4,6-dimethoxypyrimidin-2-ylcarbamoyl-sulfamoyl)-1-methylpyrazole-4-carboxylate(see EP 282613),

methyl5-(4,6-dimethylpyrimidin-2-ylcarbamoylsulfamoyl)-1-(2-pyridyl)pyrazole-4-carboxylate(NC-330, see Brighton Crop Prot. Conference--Weeds--1991, Vol. 1, 45ff.),

B4) Sulfonediamide derivatives, for example,

3-(4,6-dimethoxypyrimidin-2-yl)-1-(N-methyl-N-methylsulfonylaminosulfonyl)urea(amidosulfuron) and structural analogs (see EP-A-0131258 and Z. Pfl.Krankh. Pfl. Schutz 1990, Special Issue XII, 489-497),

B5) Pyridylsulfonylurea, for example

1-(3-N,N-dimethylaminocarbonylpyridin-2-ylsulfonyl)-3-(4,6-dimethoxypyrimidin-2-yl)urea(nicosulfuron),

1-(3-ethylsulfonylpyridin-2-ylsulfonyl)-3-(4,6-dimethoxypyrimidin-2-yl)urea(DPX-E9636, see Brighton Crop Prot. Conf.--Weeds--1989, pp. 23 ff.),

Pyridylsulfonylureas, as described in DE-A-4000503 and DE-A-4030577,preferably those of the formula ##STR11## in which E is CH or N,preferably CH,

R¹¹ is iodine or NR¹⁶ R¹⁷,

R¹² is H, halogen, cyano, C₁ -C₃ -alkyl, C₁ -C₃ -alkoxy, C₁ -C₃-haloalkyl, C₁ -C₃ -haloalkoxy, C₁ -C₃ -alkylthio, (C₁ -C₃ -alkoxy)-C₁-C₃ -alkyl, (C₁ -C₃ -alkoxy)carbonyl, mono- or di(C₁ -C₃ -alkyl)amino,C₁ -C₃ -alkylsulfinyl or -sulfonyl, SO₂ --NR^(a) R^(b) or CO--NR^(a)R^(b), in particular H,

R^(a) and R^(b), independent of one another, are H, C₁ -C₃ -alkyl, C₁-C₃ -alkenyl, C₁ -C₃ -alkynyl, or together are --(CH₂)₄ --, --(CH₂)₅ --or --(CH₂)₂ --O--(CH₂)₂ --,

R¹³ is H or CH₃,

R¹⁴ is halogen, C₁ -C₂ -alkyl, C₁ -C₂ -alkoxy, C₁ -C₂ -haloalkyl,preferably CF₃, or C₁ -C₂ -haloalkoxy, preferably OCHF₂ or OCH₂ CF₃,

R¹⁵ is C₁ -C₂ -alkyl, C₁ -C₂ -haloalkoxy, preferably OCHF₂, or C₁ -C₂-alkoxy, and

R¹⁶ is C₁ -C₄ -alkyl, and

R¹⁷ is C₁ -C₄ -alkylsulfonyl or

R¹⁶ and R¹⁷ together are a chain of the formula --(CH₂)₃ SO₂ -- or--(CH₂)₄ SO₂ --,

for example, 3=(4,6-dimethoxypyrimidin-2-yl)1-(3-N-methylsulfonyl-N-methylaminopyridin-2-yl)sulfonylurea, or saltsthereof,

B6) Alkoxyphenoxysulfonylureas, as described in EP-A-0342569, preferablythose of the formula ##STR12## in which E is CH or N, preferably CH,

R¹⁸ is ethoxy, propoxy or isopropoxy,

¹⁹ is hydrogen, halogen, NO₂, CF₃, CN, C₁ -C₄ -alkyl, C₁ -C₄ -alkoxy, C₁-C₄ -alkylthio or (C₁ -C₃ -alkoxy)carbonyl, preferably in the 6-positionon the phenyl ring,

n is 1, 2 or 3, preferably 1,

R²⁰ is hydrogen, C₁ -C₄ -alkyl or C₃ -C₄ -alkenyl,

R²¹ and R²², independently of one another, are halogen, C₁ -C₂ -alkyl,C₁ -C₂ -alkoxy, C₁ -C₂ -haloalkyl, C₁ -C₂ -haloalkoxy or (C₁ -C₂-alkoxy)-C₁ -C₂ -alkyl, preferably OCH₃ or CH₃,

for example3-(4,6-dimethoxypyrimidin-2-yl)-1-(2-ethoxyphenoxy)sulfonylurea, orsalts thereof, and other related sulfonylurea derivatives, and mixturesthereof,

C) Chloroacetanilide herbicides, such as

N-methoxymethyl-2,6-diethylchloroacetanilide (alachlor),

N-(3'-methoxyprop-2'-yl)-2-methyl-6-ethylchloroacetanilide(metolachlor),

2',6'-dimethyl-N-(3-methyl-1,2,4-oxadiazol-5-ylmethyl)chloroacetanilide

N-(2,6-dimethylphenyl)-N-(1-pyrazolylmethyl)chloroacetamide(metazachlor),

D) Thiocarbamates, such as

S-ethyl N,N-dipropylthiocarbamate (EPTC) or

S-ethyl N,N-diisobutylthiocarbamate (butylate),

E) Cyclohexanedione derivatives, such as methyl3-(1-allyloxyiminobutyl)-4-hydroxy-6,6-dimethyl-2-oxocyclohex-3-enecarboxylate(alloxydim),

2-(1-ethoxyiminobutyl)-5-(2-ethylthiopropyl)-3-hydroxycyclohex-2-en-1-one(sethoxydim),

2-(1-ethoxyiminobutyl)-5-(2-phenylthiopropyl)-3-hydroxycyclohex-2-en-1-one(cloproxydim),

2-(1-(3-chloroallyloxy)iminobutyl)-5-2-(ethylthio)propyl!-3-hydroxycyclohex-2-en-1-one,

2-(1-(3-chloroallyloxy)iminopropyl)-5-2-(ethylthio)propyl!-3-hydroxycyclohex-2-en-1-one (clethodim),

2-(1-(ethoxyimino)butyl)-3-hydroxy-5-(thian-3-yl)cyclohex-2-enone(cycloxydim) or

2-(1-ethoxyiminopropyl)-5-(2,4,6-trimethylphenyl)-3-hydroxycyclohex-2-en-1-one(tralkoxydim),

F) 2-(4-alkyl-5-oxo-2-imidazolin-2-yl)benzoic acid derivatives or2-(4-alkyl-5-oxo-2-imidazolin-2-yl)heteroarylcarboxylic acidderivatives, such as, for example,

methyl 2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)-5-methylbenzoateand

2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)--4methylbenzoic acid(imazamethabenz),

5-ethyl-2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)pyridine-3-carboxylicacid (imazathapyr),

2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)quinoline-3-carboxylicacid (imazaquin),

2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)pyridine-3-carboxylicacid (imazapyr),

5-methyl-2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)pyridine-3-carboxylicacid (imazethamethapyr),

G) Triazolopyrimidinesulfonamide derivatives, for example

N-(2,6-difluorophenyl)-7-methyl-1,2,4-triazolo-(1,5-c)-pyrimidine-2-sulfonamide(flumetsulam),

N-(2,6-dichloro-3-methylphenyl)-5,7-dimethoxy-1,2,4-triazolo-(1,5-c)-pyrimidine-2-sulfonamide,

N-(2,6-difluorophenyl)-7-fluoro-5-methoxy-1,2,4-triazolo-(1,5-c)-pyrimidine-2-sulfonamide,

N-(2,6-dichloro-3-methylphenyl)-7-chloro-5-methoxy-1,2,4-triazolo-(1,5-c)-pyrimidine-2-sulfonamide,

N-(2-chloro-6-methoxycarbonyl)-5,7-dimethyl-1,2,4-triazolo-(1,5-c)-pyrimidine-2-sulfonamide(see, for example, EP-A-343 752, and U.S. Pat. No. 4,988,812),

H) Benzoylcyclohexanedione derivatives, for example

2-(2-chloro-4-methylsulfonylbenzoyl)cyclohexane-1,3-dione (SC-0051, seeEP-A-137963),

2-(2-nitrobenzoyl)-4,4-dimethylcyclohexane-1,3-dione (see EP-A-274634),

2-(2-nitro-3-methylsulfonylbenzoyl)-4,4,-dimethylcyclohexane-1,3-dione(see W0-91/13548),

J) Pyrimidinyloxypyrimidinecarboxylic acid derivatives andpyrimidinyloxybenzoic acid derivatives, for example benzyl3-(4,6-dimethoxypyrimidin-2-yl)oxypyridine-2-carboxylate (EP-A-249 707),

methyl 3-(4,6-dimethoxypyrimidin-2-yl)oxypyridine-2-carboxylate(EP-A-249 707),

2,6-bis (4,6-dimethoxypyrimidin-2-yl)oxy!benzoic acid (EP-A 321 846),

1-ethoxycarbonyloxyethyl 2,6-bis(4,6-dimethoxypyrimidin-2-yl)oxy!benzoate (EP-A-472 113), and

K) S-(N-aryl-N-alkylcarbamoylmethyl)dithiophosphoric esters, such as

S- N-(4-chlorophenyl)-N-isopropylcarbamoylmethyl!O,O-dimethyldithiophosphate (anilofos).

The abovementioned herbicides from groups A to K are known to personsskilled in the art and are generally described in "The PesticideManual", British Crop Protection Council, 9th Edition, 1991, or 8thEdition, 1987, or in "Agricultural Chemicals Book II, Herbicides", by W.T. Thompson, Thompson Publications, Fresno Calif., U.S.A., 1990, or in"Farm Chemicals Handbook '90", Meister Publishing Company, Willoughby,Ohio, U.S.A., 1990. Imazethamethapyr is disclosed in Weed Techn. 1991,vol. 5,430-438.

The herbicidal active compounds and the safeners mentioned can beapplied together (as a ready-to-use formulation or in the tank-mixmethod) or in any desired sequence one after the other. Thesafener:herbicide weight ratio can vary within broad limits and ispreferably in the range from 1:10 to 10:1, in particular from 1:10 to5:1. The optimum amounts of both herbicide and safener depend on thetype of herbicide used and on the safener used and on the type of plantcrop to be treated and can be determined from case to case byappropriate preliminary experiments.

The main areas of application of the safeners are in particular cerealcrops (wheat, rye, barley and oats), rice, corn, sorghum, but alsocotton and soybeans, preferably cereals, rice and corn.

A particular advantage of the safeners of the formula I according to theinvention is observed when they are combined with herbicides from thegroup consisting of the sulfonylureas and/or imidazolinones and withherbicides of the phenoxyphenoxy- andheteroaryloxyphenoxyalkanecarboxylic acid derivative type.

Some herbicides from these structural classes cannot be employedselectively or not sufficiently selectively, specifically in cerealcrops and/or maize and rice. Combination with the safeners according tothe invention allows excellent selectivities to be achieved in cereals,corn or rice, even for these herbicides.

The safeners of the formula I, depending on their properties, can beused for pretreatment of seed of the crop plant (seed dressing) orintroduced into the seed drills before sowing or applied together withthe herbicide before or after emergence of the plants. Preemergencetreatment includes both treatment of the cultivated area before sowingand treatment of the sown cultivated areas, but before growth appears.Joint application with the herbicide is preferred. To this end, tankmixes and ready mixes can be employed.

The safener application rates required can vary within broad limits,depending on the indication and herbicide used and are generally in therange from 0.001 to 5 kg, preferably from 0.005 to 0.5 kg, of activecompound per hectare.

The present invention therefore also relates to a process for protectingcrop plants against phytotoxic side-effects of herbicides, whichcomprises applying effective amounts of a compound of the formula I tothe plants, plant seeds or cultivated area before, after orsimultaneously with the herbicide.

The invention also relates to crop-protection agents which contain anactive compound of the formula I and conventional formulationauxiliaries, and to herbicides which contain an active compound of theformula I and a herbicide and, in the area of the crop protection,conventional formulation auxiliaries.

The compounds of the formula I and their combinations with one or moreof said herbicides can be formulated in various ways, depending on whichbiological and/or chemical-physical parameters are pre-specified.Examples of suitable possible formulations are: wettable powders (WP),emulsifiable concentrates (EC), water-soluble powders (SP),water-soluble concentrates (SL), concentrated emulsions (EW), such asoil-in-water and water-in-oil emulsions, sprayable solutions oremulsions, capsule suspensions (CS), oil- or water-based dispersions(SC), suspoemulsions, suspension concentrates, dusts (DP), oil-misciblesolutions (OL), dressings, granules (GR) in the form of microgranules,sprayable granules, coated granules and adsorption granules, granulesfor soil application or broadcasting, water-soluble granules (SG), alsowater-dispersible granules (WG), ULV formulations, microcapsules andwaxes.

These individual formulation types are known in principle and aredescribed, for example, in: Winnacker-Kuchler, "Chemische Technologie"Chemical Technology!, Volume 7, C. Hauser Verlag, Munich, 4th Edn.,1986; Wade van Valkenburg, "Pesticide Formulations", Marcel Dekker, NewYork, 1973; K. Martens, "Spray Drying Handbook", 3rd ed., 1979, G.Goodwin Ltd., London.

The formulation auxiliaries required, such as inert materials,surfactants, solvents and further additives, are likewise known and aredescribed, for example, in: Watkins, "Handbook of Insecticide DustDiluents and Carriers", 2nd Ed., Darland Books, Caldwell N.J.; H.v.Olphen, "Introduction to Clay Colloid Chemistry", 2nd Ed., J. Wiley &Sons, New York; Marsden, "Solvents Guide", 2nd Ed., Interscience, NewYork 1963; McCutcheon's "Detergents and Emulsifiers Annual", MC Publ.Corp., Ridgewood N.J.; Sisley and Wood, "Encyclopedia of Surface ActiveAgents", Chem. Publ. Co. Inc., New York 1964; Schunfeldt,"Grenzfluchenaktive Tuthylenoxidaddukte", Surface-active Ethylene OxideAdducts!, Wiss. Verlagsgesell., Stuttgart 1976; Winnacker-Kuchler"Chemische Technologie", Chemical Technology!, Volume 7, C. HauserVerlag Munich, 4th Edn., 1986.

Based on these formulations, combinations with other pesticidally activesubstances, fertilizers and/or growth regulators can also be prepared,for example in the form of a ready mix or a tank mix.

Wettable powders are uniformly water-dispersible preparations which,besides the active compound and in addition to a diluent or inertsubstance, also contain wetting agents, for example polyoxyethylatedalkylphenols, polyoxyethylated fatty alcohols and fatty amines, fattyalcohol polyglycol ether sulfates, alkanesulfonates oralkylarylsulfonates, and dispersants, for example sodiumligninsulfonate, sodium 2,2-dinaphthylmethane-6-6'-disulfonate, sodiumdibutylnaphthalenesulfonate or sodium oleoylmethyltaurate.

Emulsifiable concentrates are prepared by dissolving the active compoundin an organic solvent, for example butanol, cyclohexanone,dimethylformamide, xylene or relatively high-boiling aromatic compoundsor hydrocarbons, with addition of one or more emulsifiers. Examples ofemulsifiers which can be used are: calcium alkylarylsulfonates, such asCa dodecylbenzenesulfonate, or nonionic emulsifiers, such as fatty acidpolyglycol esters, alkylaryl polyglycol ethers, fatty alcohol polyglycolethers, propylene oxide-ethylene oxide condensation products, (forexample block polymers), alkylpolyethers, sorbitan fatty acid esters,polyoxyethylenesorbitan fatty acid esters or polyoxyethylenesorbitolesters.

Dusts are obtained by grinding the active compound with finely dividedsolids, for example talc, natural clays, such as kaolin, bentonite andpyrophyllite, or diatomaceous earth.

Granules can be prepared either by spraying the active compound ontoadsorptive, granulated inert material or by applying active compoundconcentrates to the surface of support materials, such as sand,kaolinites or granulated inert material, by means of adhesives, forexample polyvinyl alcohol, sodium polyacrylate or mineral oils. Suitableactive compounds can also be granulated in the usual way for thepreparation of fertilizer granules--if desired as a mixture withfertilizers.

The agrochemical preparations generally contain from 0.1 to 99% byweight, in particular from 0.1 to 95% by weight, of active compounds ofthe formula I (antidote) and of the antidote/herbicide active compoundmixture and from 1 to 99.9% by weight, in particular from 5 to 99.8% byweight, of a solid or liquid additive and from 0 to 25% by weight, inparticular from 0.1 to 25% by weight, of a surfactant.

In wettable powders, the active compound concentration is, for example,from about 10 to 90% by weight, the remainder to 100% by weightcomprising conventional formulation constituents. In the case ofemulsifiable concentrates, the active compound concentration is fromabout 1 to 80% by weight of active compounds. Dust-form formulationscontain from about 1 to 20% by weight of active compounds, sprayablesolutions from about 0.2 to 20% by weight of active compounds. In thecase of granules, such as water-dispersible granules, the activecompound content depends partly on whether the active compound is inliquid or solid form. In general, the content in the case ofwater-dispersible granules is between 10 and 90% by weight.

In addition, said active compound formulations may contain theadhesives, wetting agents, dispersants, emulsifiers, penetrants,solvents, fillers or support materials which are conventional in eachcase.

For application, the formulations, in commercially available form, are,if appropriate, diluted in a conventional manner, for example by meansof water in the case of wettable powders, emulsifiable concentrates,dispersions and water-dispersible granules. Dust-form preparations,granules and sprayable solutions are not usually further diluted withfurther inert substances before application. The "antidote" applicationrate necessary varies, inter alia, with the external conditions, such astemperature, humidity and the type of herbicide used.

The samples below serve to illustrate the invention:

A. Formulation examples

a) A dust is obtained by mixing 10 parts by weight of a compound of theformula I or of an active compound mixture comprising a herbicide and acompound of the formula I and 90 parts by weight of talc as inertmaterial and comminuting the mixture in a hammer mill.

b) A readily water-dispersible wettable powder is obtained by mixing 25parts by weight of a compound of the formula I or of an active compoundmixture comprising a herbicide and a safener of the formula I, 64 partsby weight of kaolin-containing quartz as inert material, 10 parts byweight of potassium ligninsulfonate and 1 part by weight of sodiumoleoylmethyltaurate as wetting agent and dispersant, and grinding themixture in a pin mill.

c) A readily water-dispersible dispersion concentrate is obtained bymixing 20 parts by weight of the compound of formula I or of an activecompound mixture comprising a herbicide and a safener of the formula I,6 parts by weight of alkylphenol polyglycol ether (®Triton X 207), 3parts by weight of isotridecanol polyglycol ether (8 EO) and 71 parts byweight of paraffinic mineral oil (boiling range for example, from about255° to above 277° C.), and grinding the mixture to a fineness of lessthan 5 microns in a ball attrition mill.

d) An emulsifiable concentrate is obtained from 15 parts by weight of acompound of the formula I or of an active compound mixture comprising aherbicide and a safener of the formula I, 75 parts by weight ofcyclohexanone as solvent and 10 parts by weight of oxyethylatednonylphenol as emulsifier.

e) Water-dispersible granules are obtained by mixing

75 parts by weight of a compound of the formula I or of an activecompound mixture comprising a herbicide and a safener of the formula I,

10 parts by weight of calcium ligninsulfonate,

5 parts by weight of sodium lauryl sulfate,

3 parts by weight of polyvinyl alcohol and

7 parts by weight of kaolin,

grinding the mixture in an pin mill, and granulating the powder in afluidized bed by spraying on water as granulation liquid.

f) Water-dispersible granules are also obtained by homogenizing andprecomminuting

25 parts by weight of a compound of the formula I or of an activecompound mixture comprising herbicides and a safener of the formula I,

5 parts by weight of sodium 2,2'-dinaphthylmethane-6,6'-disulfonate

2 parts by weight of sodium oleoylmethyitaurate,

1 part by weight of polyvinyl alcohol,

17 parts by weight of calcium carbonate and

50 parts by weight of water,

subsequently grinding the mixture in a bead mill, and atomizing theresultant suspension in a spray tower by means of a one-component nozzleand drying it.

B. Preparation examples

1. Diethyl 2-phenoxymalonate (Example 2 from Table 1)

22.1 g (160 mmol) of potassium carbonate were suspended in 30 ml ofacetone, 7.5 g (80 mmol) of phenol in 100 ml of acetone were added, andthe mixture was refluxed for 1 hour. 15.5 g (80 mmol) of diethyl2-chloromalonate in 100 ml of acetone were subsequently added dropwise,the mixture was refluxed for 10 hours and evaporated in vacuo, and theresidue was taken up in methylene chloride. The organic phase was washedwith saturated NaHCO₃ solution and saturated NaCl solution, dried overmagnesium sulfate and evaporated. Column chromatography (silica gel,heptane/diethyl ether 2:1) of the residue gave 15.5 g (77% of theory)diethyl 2-phenoxymalonate as a colorless liquid.

2. Ethyl 2-(3,4-dichlorophenoxy)-3-ketobutanoate (Example 38 from Table1)

13.0 g (80 mmol) of 3,4-dichlorophenol and 12.2 g (88 mmol) of potassiumcarbonate were refluxed for 30 minutes in 400 ml of acetone. 15.8 g (96mmol) of ethyl 2-chloroacetoacetate were subsequently added dropwise,the mixture was refluxed for 8 hours and evaporated in vacuo, and waterwas added to the residue. The aqueous phase was extracted three timeswith ethyl acetate, and the combined organic phases were dried overmagnesium sulfate and evaporated. Column chromatography of the residuegave 15.8 g (68% of theory) of ethyl2-(3,4-dichlorophenoxy)-3-ketobutanate as an oil.

Tables 1 and 2 below show the abovementioned preparation examples withfurther examples of compounds of the formula I prepared analogously.

                                      TABLE 1                                     __________________________________________________________________________     ##STR13##                                                                    Abbreviations used: Bz = benzyl                                                                                                         m.p.                                                                           °C.!        Ex. X      (U).sub.o     R.sup.1        R.sup.2       R.sup.3                                                                           (n.sub.D                                                                      .sup.30)            __________________________________________________________________________     1  O      H             COOH           COOH          H                        2  O      H             COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H   (1.4902)             3  O      H             COOC.sub.2 H.sub.5                                                                           COOCH(CH.sub.3)(CH.sub.2).sub.4                                               CH.sub.3      H   (1.4765)             4  O      H             COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COOCH(CH.sub.3)(CH.sub.2).sub.4                                               CH.sub.3      H   (1.4700)             5  O      4-Cl          COOH           COOH          H                        6  O      4-Cl          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H   (1.5000)             7  O      4-Cl          COOC.sub.2 H.sub.5                                                                           COOCH(CH.sub.3)(CH.sub.2).sub.4                                               CH.sub.3      H   (1.4869)             8  O      4-Cl          COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COOCH(CH.sub.3)(CH.sub.2).sub.4                                               CH.sub.3      H   (1.4790)             9  O      4-Cl          COOCH.sub.2 CHCH.sub.2                                                                       COOCH.sub.2 CHCH.sub.2                                                                      H                       10  O      4-Cl          COOC.sub.4 H.sub.9 (n)                                                                       COOC.sub.4 H.sub.9 (n)                                                                      H                       11  O      4-Cl          COOC.sub.8 H.sub.17 (i)                                                                      COOC.sub.8 H.sub.17 (i)                                                                     H                       12  O      4-Cl          COOH           COOH          CH.sub.3                13  O      4-Cl          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          CH.sub.3                                                                          (1.4920)            14  O      4-Cl          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          Bz                      15  O      4-Cl          COOC.sub.2 H.sub.5                                                                           COCH.sub.3    H   n.sub.D .sup.21                                                               :                                                                             1.5162              16  O      4-Cl          COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COCH.sub.3    H                       17  O      4-Cl          COOC.sub.2 H.sub.5                                                                           COCH.sub.2 C.sub.6 H.sub.5                                                                  H                       18  O      4-Cl          COOC.sub.2 H.sub.5                                                                           C(NOH)CH.sub.3                                                                              H                       19  O      4-Cl          COOC.sub.2 H.sub.5                                                                           C(OC.sub.2 H.sub.5).sub.2                                                     CH.sub.3      H                       20  O      4-Cl          COCH.sub.3     COCH.sub.3    H                       21  O      4-Cl          C(NOH)CH.sub.3 C(NOH)CH.sub.3                                                                              H                       22  O      4-Cl          COOC.sub.2 H.sub.5                                                                           CN            H                       23  O      4-Cl          CN             CN            H                       24  O      2,4-Cl.sub.2  COOH           COOH          H                       25  O      2,4-Cl.sub.2  COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H   (1.5139)            26  O      2,4-Cl.sub.2  COOC.sub.2 H.sub.5                                                                           COOCH(CH.sub.3)(CH.sub.2).sub.4                                               CH.sub.3      H   (1.4931)            27  O      2,4-Cl.sub.2  COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COOCH(CH.sub.3)(CH.sub.2).sub.4                                               CH.sub.3      H   (1.4837)            28  O      2,4-Cl.sub.2  COOH           COCH.sub.3    H                       29  O      2,4-Cl.sub.2  COOC.sub.2 H.sub.5                                                                           COCH.sub.3    H                       30  O      2,4-Cl.sub.2  COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COCH.sub.3    H                       31  O      2,4-Cl.sub.2  COONa          COCH.sub.3    H                       32  O      2,4-Cl.sub.2  COOK           COCH.sub.3    H                       33  O      2,4-Cl.sub.2  COOC.sub.2 H.sub.5                                                                           CN            H                       34  O      2,4-Cl.sub.2  CN             CN            H                       35  O      2,4-Cl.sub.2  COCH.sub.3     COCH.sub.3    H                       36  O      3,4-Cl.sub.2  COOH           COOH          H                       37  O      3,4-Cl.sub.2  COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H   (1.5117)            38  O      3,4-Cl.sub.2  COOC.sub.2 H.sub.5                                                                           COOCH(CH.sub.3)(CH.sub.2).sub.4                                               CH.sub.3      H   (1.4950)            39  O      3,4-Cl.sub.2  COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COOCH(CH.sub.3)(CH.sub.2).sub.4CH.                                            sub.3         H   (1.4857)            40  O      3,4-Cl.sub.2  COOC.sub.2 H.sub.5                                                                           COCH.sub.3    H   n.sub.D .sup.21                                                               :                                                                             1.5131              41  O      3,4-Cl.sub.2  COOCH(CH.sub.3)(CH.sub.2).sub.4CH.sub.3                                                      COCH.sub.3    H                       42  O      3,4-Cl.sub.2  COOC.sub.2 H.sub.5                                                                           C(OC.sub.2 H.sub.5).sub.2                                                     CH.sub.3      H                       43  O      3,4-Cl.sub.2  CN             CN            H                       44  O      3,4-Cl.sub.2  CN             COOC.sub.2 H.sub.5                                                                          H                       45  O      2-CH.sub.3, 4-Cl                                                                            COOH           COOH          H                       46  O      2-CH.sub.3, 4-Cl                                                                            COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       47  O      2-CH.sub.3, 4-Cl                                                                            COOC.sub.2 H.sub.5                                                                           COOCH(CH.sub.3)(CH.sub.2).sub.4                                               CH.sub.3      H                       48  O      2-CH.sub.3, 4-Cl                                                                            COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COOCH(CH.sub.3)(CH.sub.2).sub.4CH.                                            sub.3         H                       49  O      2-CH.sub.3, 4-Cl                                                                            COOC.sub.2 H.sub.5                                                                           COCH.sub.3    H                       50  O      4-F           COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       51  O      4-F           COOC.sub.2 H.sub.5                                                                           COOCH(CH.sub.3)(CH.sub.2).sub.4                                               CH.sub.3      H                       52  O      4-F           COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COOCH(CH.sub.3)(CH.sub.2).sub.4CH.                                            sub.3         H                       53  O      4-F           COOC.sub.2 H.sub.5                                                                           COCH.sub.3    H                       54  O      4-Br          COOH           COOH          H                       55  O      4-Br          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H   (1.5160)            56  O      4-Br          COOC.sub.2 H.sub.5                                                                           COOCH(CH.sub.3)(CH.sub.2).sub.4                                               CH.sub.3      H   (1.4969)            57  O      4-Br          COOCH(CH.sub.3).sub.2 (CH.sub.2).sub.4 CH.sub.3                                              COOCH(CH.sub.3 (CH.sub.2).sub.4                                               CH.sub.3      H   (1.4877)            58  O      4-Br          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          CH.sub.3                59  O      4-Br          COOC.sub.2 H.sub.5                                                                           COCH.sub.3    H   (1.5321)            60  O      4-Br          COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COCH.sub.3    H                       61  O      4-Br          COCH.sub.3     COCH.sub.3    H                       62  O      4-Br          CN             COOC.sub.2 H.sub.5                                                                          H                       63  O      4-Br          CN             CN            H                       64  O      4-CH.sub.3    COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       65  O      4-CH.sub.3    COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COOCH(CH.sub.3)(CH.sub.2).sub.4CH.                                            sub.3         H                       66  O      4-OC.sub.2 H.sub.5                                                                          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       67  O      4-OC.sub.2 H.sub.5                                                                          COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COOCH(CH.sub.3)(CH.sub.2).sub.4CH.                                            sub.3         H                       68  O      2-Cl, 4-CF.sub.3                                                                            COOH           COOH          H                       69  O      2-Cl, 4-CF.sub.3                                                                            COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       70  O      2-Cl, 4-CF.sub.3                                                                            COOC.sub.2 H.sub.5                                                                           COOCH(CH.sub.3)(CH.sub.2).sub.4CH.                                            sub.3         H                       71  O      2-Cl, 4-CF.sub.3                                                                            COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COOCH(CH.sub.3)(CH.sub.2).sub.4CH.                                            sub.3         H                       72  O      2-Cl, 4-CF.sub.3                                                                            COOC.sub.2 H.sub.5                                                                           COCH.sub.3    H                       73  O      3-Br          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       74  O      3-I           COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       75  O      2-F           COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       76  O      2-Cl          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       77  O      2-Cl          COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COOCH(CH.sub.3)(CH.sub.2).sub.4CH.                                            sub.3             H                   78  O      2-Cl          COOC.sub.2 H.sub.5                                                                           COCH.sub.3    H                       79  O      4-NO.sub.2    COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       80  O      2-NO.sub.2    COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       81  O      2-NO.sub.2, 4-Cl                                                                            COOH           COOH          H                       82  O      2-NO.sub.2, 4-Cl                                                                            COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       83  O      2-NO.sub.2, 4-Cl                                                                            COOC.sub.2 H.sub.5                                                                           COOCH(CH.sub.3)(CH.sub.2).sub.4CH.                                            sub.3         H                       84  O      2-NO.sub.2, 4-Cl                                                                            COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COOCH(CH.sub.3)(CH.sub.2).sub.4CH.                                            sub.3         H                       85  O      2-NO.sub.2, 4-Cl                                                                            COOC.sub.2 H.sub.5                                                                           COCH.sub.3    H                       86  O      2-NO.sub.2, 4-Cl                                                                            COOC.sub.2 H.sub.5                                                                           C(NOH)CH.sub.3                                                                              H                       87  O      2-NO.sub.2, 4-Cl                                                                            CN             CN            H                       88  O      2-NO.sub.2, 4-Cl                                                                            COOC.sub.2 H.sub.5                                                                           CN            H                       89  O      2-NH.sub.2, 4-Cl                                                                            COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       90  O      2-N(CH.sub.3).sub.2, 4-Cl                                                                   COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       91  S      H             COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       92  S      4-Cl          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H   b.p. (0.1)                                                                    140-145°     93  S      4-Cl          CN             CN            H                       94  S      4-Br          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       95  S      2,5-Cl.sub.2  COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       96  NH     4-Cl          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H   94-95               97  NH     2,4-Cl.sub.2  COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       98  NH     3-Cl          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       99  NH     3,4-Cl.sub.2  COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       100 NCH.sub.3                                                                            4-Cl          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       101 NCH(CH.sub.3).sub.2                                                                  4-Cl          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       102 NCH(CH.sub.3).sub.2                                                                  4-Cl          COOC.sub.2 H.sub.5                                                                           COOCH(CH.sub.3)(CH.sub.2).sub.4CH.                                            sub.3         H                       103 NCH(CH.sub.3).sub.2                                                                  4-Cl          COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COOCH(CH.sub.3)(CH.sub.2).sub.4CH.                                            sub.3         H                       104 NHNH   4-Cl          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       105 NHNH   3,4-Cl.sub.2  COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       106 NHNH   2,4-Cl.sub.2  COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       107 NHNH   4-Br          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H                       108 O      3-Cl          COOC.sub.2 H.sub.5                                                                           COCH.sub.3    H                       109 O      3-Cl          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H   (1.5016)            110 O      3-Cl          COOC.sub.2 H.sub.5                                                                           COOCH(CH.sub.3)(CH.sub.2).sub.4CH.                                            sub.3         H   (1.4838)            111 O      3-Cl          COOCH(CH.sub.3)(CH.sub.2).sub.4 CH.sub.3                                                     COOCH(CH.sub.3)(CH.sub.2).sub.4CH.                                            sub.3         H   (1.4719)            112 O      3-Cl          COOC.sub.2 H.sub.5                                                                           CN            H                       113 O      3-Cl          CN             CN            H                       114 O                                                                                     ##STR14##    COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          H   resin               115 O      "             COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          CH.sub.3                                                                          oil                 116 S      4-Cl          COOC.sub.2 H.sub.5                                                                           COOC.sub.2 H.sub.5                                                                          SC.sub.6 H.sub.4                                                                  77-80                                                                     p-Cl                    __________________________________________________________________________

                                      TABLE 2                                     __________________________________________________________________________     ##STR15##                                                                    Abbreviation used: Bz = benzyl                                                                                          m.p.  °C.!                   Ex.                                                                              Ar        X R.sup.1     R.sup.2     R.sup.3                                                                          (n.sub.D .sup.30                    __________________________________________________________________________                                              )                                    1                                                                                ##STR16##                                                                              O COOH        COOH        H                                       2 "         O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        H                                       3 "         O COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         H                                                     CH.sub.3    CH.sub.3                                            4 "         O COOCH.sub.2 CHCH.sub.2                                                                    COOCH.sub.2 CHCH.sub.2                                                                    H                                       5 "         O COOC.sub.4 H.sub.9 (n)                                                                    COOC.sub.4 H.sub.9 (n)                                                                    H                                       6 "         O COOC.sub.8 H.sub.17 (i)                                                                   COOC.sub.8 H.sub.17 (i)                                                                   H                                       7 "         O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        CH.sub.3                                8 "         O COOC.sub.2 H.sub.5                                                                        COCH.sub.3  H                                       9 "         O COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         COCH.sub.3  H                                                     CH.sub.3                                                       10 "         O CN          CN          H                                      11 "         O COOC.sub.2 H.sub.5                                                                        CN          H                                      12                                                                                ##STR17##                                                                              O COOH        COOH        H                                      13 "         O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        H                                      14 "         O COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         H                                                     CH.sub.3    CH.sub.3                                           15 "         O COOC.sub.2 H.sub.5                                                                        COCH.sub.3  H                                      16 "         O CN          CN          H                                      17 "         O COOC.sub.2 H.sub.5                                                                        CN          H                                      18                                                                                ##STR18##                                                                              O COOH        COOH        H  147 (decomp.)                       19 "         O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        H  (1.5370)                            20 "         O COOC.sub.2 H.sub.5                                                                        COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         H  (1.5205)                                                       CH.sub.3                                           21 "         O COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         H  (1.5045)                                           CH.sub.3    CH.sub.3                                           22 "         O COOCH.sub.2 CHCH.sub.2                                                                    COOCH.sub.2 CHCH.sub.2                                                                    H                                      23 "         O COOC.sub.2 H.sub.5                                                                        COCH.sub.3  H  n.sub.D .sup.21 : 1.5570            24 "         O COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         COCH.sub.3  H  oil                                                CH.sub.3                                                       25 "         O COOC.sub.2 H.sub.5                                                                        CN          H                                      26 "         O CN          CN          H                                      27                                                                                ##STR19##                                                                              O COOH        COOH        H  226                                 28 "         O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        H  77-78                               29 "         O COOC.sub.2 H.sub.5                                                                        COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         H                                                                 CH.sub.3                                           30 "         O COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         H  (1.5145)                                           CH.sub.3    CH.sub.3                                           31 "         O COOCH.sub.2 CHCH.sub.2                                                                    COOCH.sub.2 CHCH.sub.2                                                                    H  (1.5597)                            32 "         O COOCH(CH.sub.3).sub.2                                                                     COOCH(CH.sub.3).sub.2                                                                     H  (1.5344)                            33 "         O COOC.sub.4 H.sub.9 (n)                                                                    COOC.sub.4 H.sub.9 (n)                                                                    H                                      34 "         O COOC.sub.2 H.sub.5                                                                        COOC.sub.4 H.sub.9 (t)                                                                    H                                      35 "         O COOC.sub.4 H.sub.9 (t)                                                                    COOC.sub.4 H.sub.9 (t)                                                                    H                                      36 "         O COOC.sub.8 H.sub.17 (i)                                                                   COOC.sub.8 H.sub.17 (i)                                                                   H                                      37 "         O COOC.sub.2 H.sub.5                                                                        COOC.sub.5 H.sub.9 (c)                                                                    H                                      38 "         O COOC.sub.5 H.sub.9 (c)                                                                    COOC.sub.5 H.sub.9 (c)                                                                    H  (1.5519)                            39 "         O COOCH.sub.2 C.sub.6 H.sub.5                                                               COOCH.sub.2 C.sub.6 H.sub.5                                                               H  resin                               40 "         O COOCH.sub.2 CH.sub.2 OH                                                                   COOCH.sub.2 CH.sub.2 OH                                                                   H                                      41 "         O COOCH.sub.2 CF.sub.3                                                                      COOCH.sub.2 CF.sub.3                                                                      H                                      42 "         O COOH        COOH        CH.sub.3                               43 "         O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        CH.sub.3                               44 "         O COOC.sub.2 H.sub.5                                                                        COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         CH.sub.3                                                          CH.sub.3                                           45 "         O COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         CH.sub.3                                              CH.sub.3    CH.sub.3                                           46 "         O COOH        COOH        Bz                                     47 "         O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        Bz                                     48 "         O COOC.sub.2 H.sub.5                                                                        COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         Bz                                                                CH.sub.3                                           49 "         O COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         Bz                                                    CH.sub.3    CH.sub.3                                           50 "         O COOC.sub.2 H.sub.5                                                                        COCH.sub.3  H  n.sub.D .sup.21 : 1.5700            51 "         O COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         COCH.sub.3  H  (1.5350)                                           CH.sub.3                                                       52 "         O COOC.sub.2 H.sub.5                                                                        C(NOH)CH.sub.3                                                                            H                                      53 "         O COOC.sub.2 H.sub.5                                                                        C(OC.sub.2 H.sub.5).sub.2 CH.sub.3                                                        H                                      54 "         O COOC.sub.2 H.sub.5                                                                        CN          H                                      55 "         O CN          CN          H                                      56                                                                                ##STR20##                                                                              O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        H  oil                                 57 "         O COOC.sub.2 H.sub.5                                                                        COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         H  resin                                                          CH.sub.3                                           58 "         O COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         COOCH(CH.sub.3)(CH.sub.2).sub.4 -                                                         H  resin                                              CH.sub.3    CH.sub.3                                           59                                                                                ##STR21##                                                                              O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        H  (1.5508)                            60 "         O COOC.sub.2 H.sub.5                                                                        COCH.sub.3  H                                      61                                                                                ##STR22##                                                                              O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        H  oil                                 62                                                                                ##STR23##                                                                              O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        H  oil                                 63                                                                                ##STR24##                                                                              O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        H  oil                                 64                                                                                ##STR25##                                                                              O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        H  oil                                 65                                                                                ##STR26##                                                                              O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        H  (1.5078)                            66                                                                                ##STR27##                                                                              O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        H  (1.4890)                            67                                                                                ##STR28##                                                                              S COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        H  oil                                 68 "         O COOCH.sub.3 COOC.sub.2 H.sub.5                                                                        H  (1.5558)                            69                                                                                ##STR29##                                                                              O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        H  82-83                               70                                                                                ##STR30##                                                                              O COOCH.sub.3 COOCH.sub.3 H  88.5                                71 "         O COOCH.sub.3 COOC.sub.2 H.sub.5                                                                        H  (1.5486)                            72 "         O COOCH.sub.3 COOC.sub.2 H.sub.5                                                                        CH.sub.3                               73 "         O COOCH.sub.3 COOC.sub.2 H.sub.5                                                                        Br                                     74 "         O COOCH.sub.3 COOC.sub.2 H.sub.5                                                                        C.sub.2 H.sub.5                        75 "         O COOC.sub.2 H.sub.5                                                                        COOCH.sub.2 CHCH.sub.2                                                                    H  oil                                 76 "         O COOCH.sub.2 CHCH.sub.2                                                                    COOCH.sub.2 CHCH.sub.2                                                                    CH.sub.3                               77 "         O COOC.sub.3 H.sub.7                                                                        COOC.sub.3 H.sub.7                                                                        H                                      78 "         O COOCH.sub.2 CCl.sub.3                                                                     COOCH.sub.2 CCl.sub.3                                                                     H                                      79 "         O COOCH.sub.2 CH.sub.2 Cl                                                                   COOCH.sub.2 CH.sub.2 Cl                                                                   H                                      80 "         O COOC.sub.5 H.sub.11 (n)                                                                   COOC.sub.5 H.sub.11 (n)                                                                   H                                      81                                                                                ##STR31##                                                                              O COOC.sub.2 H.sub.5                                                                        COOC.sub.2 H.sub.5                                                                        H  oil                                 __________________________________________________________________________

C. Biological examples

EXAMPLE 1

Seeds of wheat and barley were placed in sandy loam soil in plasticpots, raised to the 3- to 4-leaf stage in a greenhouse and then treatedsuccessively with the compounds according to the invention and theherbicides using the post-emergence method. The herbicides and thecompounds of the formula I were applied in the form of aqueoussuspensions or emulsions at an application rate of 300 l/ha (converted).3-4 weeks after the treatment, the plants were assessed visually fordamage of any type caused by the herbicides applied, in particular theextent of lasting growth inhibition being taken into account. Theassessment was made in percentages compared with untreated controls.Some experimental results are shown in Tables 3 and 4.

                  TABLE 3                                                         ______________________________________                                        Safener action on wheat and barley                                                      Application rate                                                    Active     g of a.i./ha!  Damage  %!                                          compound  herbicide   safener TA    HV   TD                                   ______________________________________                                        H1        400         --      40    98   98                                             200         --      30    90   95                                             100         --      10    80   95                                   H1 +      400         50      10    20   10                                   Ex. 28/Tab 2                                                                            200         25       0     0    0                                             100         12       0     0    0                                   H6 +      400         50      10    25   15                                   Ex. 31/Tab 2                                                                            200         25       0    15    0                                             100         12       0     0    0                                   H6 +      400         100     15    25   20                                   Ex. 27/Tab 2                                                                            200         50       0    10    5                                             100         25       0     0    0                                   H2        1800        --      --    40   --                                             900         --      --    10   --                                   H2 +      1800        225     --    0                                         Ex. 71/Tab 2                                                                            900         112     --    0    --                                   H3        50          --      70    60   --                                             25          --      80    30   --                                             12          --      15    20   --                                   H3 +      50          25      20    10   --                                   Ex. 28/Tab 2                                                                            25          12      10     5   --                                             12           6       0     0   --                                   H3 +      50          25      15    10   --                                   Ex. 71/Tab 2                                                                            25          12       0     0   --                                             12           6       0     0   --                                   H3 +      50          25      25    20   --                                   Ex. 75/Tab 2                                                                            25          12       5     5   --                                             12           6       0     0   --                                   H3 +      50          25      25    20   --                                   Ex. 31/Tab 2                                                                            25          12      15    10   --                                             12           6       0     0   --                                   ______________________________________                                         Key to Table 3:                                                               Test conditions: Application at the 4leaf stage; assessment after 4 weeks     4 replications                                                                Abbreviations:                                                                H1 = fenoxapropP-ethyl                                                        H2 = diclofopmethyl                                                           H3 = methyl                                                                   4iodo-2- 3-(4-methoxy-6-methy1-1,3,5-triazin-2-yl)ureidosulfonyl!benzoate     sodium salt                                                                   HV = Hordeum vulgare (barley)                                                 TA = Triticum aestivum (wheat)                                                TD = Triticum durum (hard wheat)                                              Ex. No./Tab No. = safener No. from Table No.                                  -- = not applied (in the case of safeners) or not tested (in the case of      plant crops)                                                             

                  TABLE 4                                                         ______________________________________                                        Safener action on barley                                                                   Application rate                                                                              Damage                                                         g of a.i./ha!   %!                                              Active component                                                                           herbicide   safener HV                                           ______________________________________                                        H1           200                 65                                           H1 + Ex. 27/Tab 2                                                                          200         1250    50                                           H1 + Ex. 30/Tab 2                                                                          200         1250    65                                           H1 + Ex. 50/Tab 2                                                                          200         1250    30                                           H1 + Ex. 64/Tab 2                                                                          200         1250    35                                           H1 + Ex. 70/Tab 2                                                                          200         1250    30                                           H1 + Ex. 32/Tab 2                                                                          200         1250    50                                           H1 + Ex. 75/Tab 2                                                                          200         1250    33                                           H1 + Ex. 39/Tab 2                                                                          200         1250    25                                           H1 + Ex. 19/Tab 2                                                                          200         1250    60                                           H1 + Ex. 51/Tab 2                                                                          200         1250    50                                           ______________________________________                                         Test conditions: Application at the 3leaf stage; assessment after 2-3         weeks; 4 replications                                                         Abbreviations: see abbreviations for Table 3                             

Even when the herbicide is applied in very excessive amounts, severedamage to the crop plants is significantly reduced, and slight damage iscompletely eliminated.

Mixture of herbicides and compounds according to the invention aretherefore highly suitable for selective weed control in cereal crops.

EXAMPLE 2

Corn plants, weed and weed grasses were raised to the 4- to 5-leaf stagein plastic pots outside or in the greenhouse and treated successivelywith herbicides and compounds of the formula I according to theinvention using the post-emergence method. The active compounds wereapplied in the form of aqueous suspensions or emulsions and anapplication rate of 300 l of water/ha (converted). 4 weeks after thetreatment, the plants were assessed visually for any type of damagecaused by the herbicides applied, in particular the extent of lastinggrowth inhibition being taken into account. The assessment was made inpercent compared with untreated controls. Some results are shown inTables 5 to 7.

                  TABLE 5                                                         ______________________________________                                        Safener action on corn (Zea mays)                                                      Application rate Damage to corn  %!                                  Active      g of a.i./ha!     Alois Felix                                     compound(s)                                                                              herbicide                                                                              safener   variety                                                                             variety                                   ______________________________________                                        H4         300      --        60    60                                                   150      --        55    50                                                    75      --        40    30                                                    38      --        20     0                                        H4 +       300      150       30    25                                        Ex. 28/Tab 2                                                                             150      75        10    15                                                    75      38         0     0                                                    38      19         0     0                                        H4 +       300      150       40    30                                        Ex. 31/Tab 2                                                                             150      75        15    10                                                    75      38         0     0                                                    38      19         0     0                                        H5         200      --        50    45                                                   100      --        40    35                                                    50      --        30    25                                        H5 +       200      100       20    15                                        Ex. 28/Tab 2                                                                             100      50        10     5                                                    50      25         0     0                                        H5 +       200      100       20    20                                        Ex. 71/Tab 2                                                                             100      50         5    10                                                    50      25         0     0                                        ______________________________________                                         Test conditions: Application at the 4leaf stage; assessment after 4 weeks     4 replications                                                                Abbreviations: see Table 3, and                                               H4 = benzyl 3(4,6-dimethoxypyrimidin-2-yloxy)pyridine-2-carboxylate           H5 =                                                                          5ethyl-2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)pyridine-3-carboxy    ic acid (imazethapyr)                                                     

                  TABLE 6                                                         ______________________________________                                        Safener action on corn (Zea mays)                                                     Application rate                                                                             Damage  %! in corn                                     Active   g of a.i./ha! varieties                                              compound(s)                                                                           herbicide  safener Mutin   Felix                                                                              Dea                                   ______________________________________                                        H6      80         --      40      5    --                                            40         --      20      5    --                                            20         --       5      10   --                                    H6 +    80         40      10      5    --                                    Ex. 71/Tab 2                                                                          40         20       0      0    --                                            20         10       0      0    --                                    H6 +    80         40      20      15   --                                    Ex. 70/Tab 2                                                                          40         20       5      0    --                                            20         10       0      0    --                                    H7      60         --      70      75   --                                            30         --      30      40   --                                            15         --      10      15   --                                             8         --       5       0   --                                    H7 +    60         30      20      25   --                                    Ex. 71/Tab 2                                                                          30         15       5      10   --                                            15         7.5      0       0   --                                             8         4        0       0   --                                    H7 +    60         30      25      25   --                                    Ex. 70/Tab 2                                                                          30         15      10       5   --                                            15         7.5      0       0   --                                             8         4        0       0   --                                    H8      200        --      65      70   35                                            100        --      60      65   10                                            50         --      30      55    0                                            25         --      15      25    0                                    H8 +    200        100     40      25    0                                    Ex. 31/Tab 2                                                                          100        50      20      10    0                                            50         25       0       0    0                                            25         12       0       0    0                                    H8 +    200        100     35      30    5                                    Ex. 71/Tab 2                                                                          100        50      15      10    0                                            50         25       0       0    0                                            25         12       0       0    0                                    H8 +    200        100     30      30                                         Ex. 75/Tab 2                                                                          100        50      20      10    0                                            50         25       0       0    0                                            25         12       0       0    0                                    H8 +    200        100     30      30    0                                    Ex. 28/Tab 2                                                                          100        50      20      10    0                                            50         25       0       0    0                                            25         12       0       0    0                                    ______________________________________                                         Test conditions: Application at the 4leaf stage; assessment after 4 weeks     4 replications.                                                               Abbreviations: see Table 3, and as follows                                    H6 =                                                                          1(3-ethylsulfonylpyridin-2-ylsulfonyl)-3-(4,6-dimethoxypyrimidin-2-yl)ure     (DPXE 9636, rimsulfuron)                                                      H7 =                                                                          1(2-methoxycarbonylthiophen-3-yl)-3-(4-methoxy-6-methyl-1,3,5-triazin-2-y     )urea (thifensulfuronmethyl)                                                  H8 =                                                                          3(4,6-dimethoxypyrimidin-2-yl)-1- 3(-N-methyl-N-methylsulfonylamino)-2-py    idylsulfonyl!urea                                                         

                  TABLE 7                                                         ______________________________________                                        Safener action on corn (Zea mays)                                                       Application rate Damage in                                          Active     g of a.i./ha!   corn  %!                                           compound(s)                                                                             herbicide    safener Felix variety                                  ______________________________________                                        H8        75           --      75                                             HB +      75           1250    55                                             Ex. 50/Tab 2                                                                  H8 +      75           1250    20                                             Ex. 68/Tab 2                                                                  H8 +      75           1250    55                                             Ex. 70/Tab 2                                                                  H8 +      75           1250    30                                             Ex. 19/Tab 2                                                                  ______________________________________                                         Test conditions: Application at the 3leaf stage; assessment after 3 weeks     4 replications                                                                Abbreviations: as in Table 6                                             

The results show that the compounds of the formula I according to theinvention employed can effectively reduce severe herbicide damage to thecorn plants. Even if the herbicides are applied in very excessiveamounts, severe damage to the crop plants is significantly reduced andslight damage eliminated completely. Mixtures of herbicides andcompounds of the formula I are therefore highly suitable for selectiveweed control in corn.

EXAMPLE 3

Rice was sown in plastic pots and raised in a greenhouse under optimumgrowth conditions. After emergence, the pots were filled with water to 2cm from the top, and this flooding level was maintained throughout theexperiment. At the 3- to 4-leaf stage, the plants were then treated withthe herbicides and the compounds of the formula I. 3 weeks aftertreatment, the plants were assessed for damage of any type caused by theherbicides, in particular the extent of lasting growth inhibition andthinning being considered. The results of the assessments show that thesafeners effectively reduce herbicide damage to rice. Some results areshown in Table 8.

                  TABLE 8                                                         ______________________________________                                        Safener action on rice                                                                     Application rate                                                 Active        g of a.i./ha!  Damage  %!                                       compound(s)  herbicide   safener ORSA                                         ______________________________________                                        H1           300         --      80                                           H1 + Ex. 28/Tab 2                                                                          300         1250    35                                           H1 + Ex. 27/Tab 2                                                                          300         1250    70                                           H1 + Ex. 30/Tab 2                                                                          300         1250    45                                           H1 + Ex. 50/Tab 2                                                                          300         1250    70                                           H1 + Ex. 64/Tab 2                                                                          300         1250    70                                           R1 + Ex. 70/Tab 2                                                                          300         1250    70                                           H1 + Ex. 32/Tab 2                                                                          300         1250    35                                           H1 + Ex. 75/Tab 2                                                                          300         1250    30                                           H1 + Ex. 31/Tab 2                                                                          300         1250    50                                           H1 + Ex. 39/Tab 2                                                                          300         1250    70                                           H1 + Ex. 19/Tab 2                                                                          300         1250    45                                           H1 + Ex. 51/Tab 2                                                                          300         1250    70                                           H1 + Ex. 71/Tab 2                                                                          300         1250    40                                           ______________________________________                                         Test conditions: Application at the 3leaf stage; assessment after 3 weeks     4 replications.                                                               Abbreviations: see Table 3 and                                                ORSA = Oryza sativa (rice)                                               

Mixes of herbicides and the safeners according to the invention are thussuitable for selective weed control in rice. The herbicidal activity ofthe herbicides employed against weeds are not impaired by addition ofthe safeners according to the invention; at the application rates used,it corresponds to the comparative values achieved using the herbicidesalone.

EXAMPLES 4

Rice was sown in sandy soil in pots in a greenhouse and raised to agrowth height of 24-25 cm. The rice was then transplanted into awater-covered soil and, 3 days after transplanting, treated with aherbicide or a herbicide/safener combination by watering. 4 weeks afterapplication, plant damage was assessed visually compared with untreatedcontrols (results see Table 9).

                  TABLE 9                                                         ______________________________________                                        Safener action on transplanted rice                                                     Application rate                                                    Active     g of a.i./ha!   Damage  %!                                         compound(s)                                                                             herbicide    safener ORSA-T                                         ______________________________________                                        H9        450          --      50                                             H9 +      450          225     33                                             Ex. 28/Tab 2                                                                            450          450     33                                             ______________________________________                                         Abbreviations as in Table 3, and as follows:                                  ORSAT = Oryza sativa (transplanted)                                           H9 = anilofos                                                            

The example of Table 3 illustrates the safener action of compounds offormula (I) in a herbicide which is structurally completely differentfrom herbicides H1 to H8.

What is claimed is:
 1. A selective herbicidal composition which contains one or more herbicides and one or more safeners of compounds of the formula I, or salts thereof, ##STR32## in which R¹ and R², independently of one another, are radicals of the formula ##STR33## in which R, R^(T), R⁴, R⁵, R⁶, Y, T, Z, Q, A_(i), X_(i) and q are as defined below, orR¹ and R² are bonded to one another and together are a group of the formula

    --CO--Q.sup.1 --D--Q.sup.2 --CO--

in which Q¹ and Q², independently of one another, are as defined for Q and D is a divalent group of the formula CR'R" or C═O, where R' and R", independently of one another, are hydrogen or C₁ -C₄ -alkyl, R³ is hydrogen, halogen, C₁ -C₁₈ -alkyl, C₂ -C₈ -alkenyl, C₂ -C₈ -alkynyl, C₁ -C₁₈ alkoxy, C₂ -C₈ -alkenyloxy, C₂ -C₈ -alkynyloxy, C₁ -C₁₈ -alkylthio, C₂ -C₈ -alkenylthio, C₂ -C₈ -alkynylthio, where each of the 9 last-mentioned radicals selected is in each case unsubstituted or substituted by one or more radicals selected from the group consisting of halogen, nitro and cyano, or is C₃ -C₁₂ -cycloalkyl which is unsubstituted or substituted by one or more radicals selected from the group consisting of C₁ -C₄ -alkyl, halogen, nitro and cyano, or is SiR^(a) R^(b) R^(c), in which R^(a), R^(b) and R^(c), independently of one another, are C₁ -C₄ -alkyl, C₂ -C₄ -alkenyl, C₂ -C₄ -alkynyl or substituted or unsubstituted phenyl, or is a radical of the formula Ar'X'--, in which Ar' and X' are defined analogously to Ar and X, X is O, S, NH--NH or NR^(d), where R^(d) is defined analogously to R⁴, or is --CH₂ O--, --CH₂ S--, --CH(Ar)O-- or --CH(Ar)S--, Ar is an aromatic radical, R is hydrogen or an aliphatic, aromatic, heteroaromatic, araliphatic or heteroaraliphatic radical having 1 to 30 carbon atoms and, optionally, containing one or more functional groups, R^(T) is a radical of the formula --CO--R, --CS--R, --NR^(f) R^(g), --N═CR^(h) R^(i) or SiR^(a) R^(b) R^(c), where R is as defined above, and R^(f), R^(g), R^(h) and R^(i), independently of one another are hydrogen, C₁ -C₄ -alkyl, C₂ -C₄ -alkenyl, C₂ -C₄ -alkynyl, benzyl, phenyl or substituted phenyl, or R^(f) and R^(g) together with the nitrogen atom are a 5- or 6-membered heterocyclic ring which may contain up to 2 further heteroatoms from the group consisting of N, O and S, and which may be substituted by C₁ -C₄ -alkyl, andR^(a), R^(b) and R^(c), independently of one another, are C₁ -C₄ -alkyl, C₂ -C₄ -alkenyl, C₂ -C₄ -alkynyl, phenyl or substituted phenyl, Y and Z, independently of one another, are oxygen, sulfur in its various oxidation states or --NR^(e), where R^(e) is defined analogously to R⁴, R⁴ and R⁵ are identical or different and, independently of one another, are hydrogen, C₁ -C₆ -alkyl, C₂ -C₆ -alkenyl, C₂ -C₆ -alkynyl, (C_(l) -C₆ -alkyl)-carbonyl, where each of the 4 last-mentioned radicals is unsubstituted or substituted by one or more substituents selected from the group consisting of halogen, C₁ -C₈ -haloalkoxy, nitro, cyano, hydroxyl, C₁ -C₈ -alkoxy and C₁ -C₈ -alkoxy, in which one or more CH₂ groups which are not bonded directly to one another are replaced by oxygen, and C₁ -C₈ -alkylthio, C₁ -C₆ -alkylsulfonyl, C₂ -C₈ -alkenylthio, C₂ -C₈ -alkynylthio, C₂ -C₈ -alkenyloxy, C_(2-C) ₈ -alkynyloxy, C₃ -C₇ -cycloalkyl, C₃ -C₇ -cycloalkoxy and amino, mono- and di-(C_(l) -C₄ -alkyl)amino, or are formyl, SiR^(a) R^(b) R^(c), in which R^(a), R^(b) and R^(c), independently of one another, are C₁ -C₄ -alkyl, C₂ -C₄ -alkenyl, C₂ -C₄ -alkynyl or substituted or unsubstituted phenyl, or are C₃ -C₈ -cycloalkyl, C₃ -C₈ -cycloalkenyl, heterocyclyl having 3 to 7 ring atoms, aryl, heteroaryl or arylcarbonyl, where each of the 6 last-mentioned radicals is unsubstituted or substituted by one or more radicals selected from the group consisting of C₁ -C₈ -alkyl, halogen, C₁ -C₈ -haloalkoxy, nitro, cyano, hydroxyl, C₁ -C₈ -alkoxy and C₁ -C₈ -alkoxy, in which one or more, CH₂ groups which are not bonded directly to one another are replaced by oxygen, and C₁ -C₈ -alkylthio, C₁ -C₆ -alkylsulfonyl, C₂ -C₈ -alkenylthio, C₂ -C₈ -alkynylthio, C₂ -C₈ -alkenyloxy, C₂ -C₈ -alkynyloxy, C₃ -C₇ -cycloalkyl, C₃ -C₇ -cycloalkoxy, and amino, mono- and di-(C₁ -C₄ -alkyl)amino, or R⁴ and R⁵ together are a C₂ -C₄ -alkene chain or a C₂ -C₄ -alkenylene chain which is unsubstituted or substituted by 1 or 2 radicals selected from the group consisting of methyl, ethyl, methoxy, ethoxy and halogen, R⁶ is hydrogen, C₁ -C₄ -alkyl, C₂ -C₄ -alkenyl, C₂ -C₄ -alkynyl, C₆ -C₁₂ -aryl, heteroaryl, benzyl, C₁ -C₄ alkoxy, acyloxy, hydroxyl, --NH--CO--NH₂, --NH--CS--NH₂, mono- and di-(C₁ -C₄ -alkyl)amino, --NH-acyl, --NHSO₂ --(C₁ -C₄ -alkyl), C₆ -C₁₂ -aryloxy, heteroaryloxy, NH--SO₂ aryl, or NH-aryl, in which aryl or heteroaryl in the 4 last-mentioned radicals is unsubstituted or substituted by one or more radicals selected from the group consisting of halogen, nitro, (C₁ -C₄)-alkyl, (C₁ -C₄)-alkoxy, (C₁ -C₄)-haloalkyl and (C₁ -C₄)-haloalkoxy, T is O, S, NR⁷, NOR⁷ or NO-acyl, Q is O or S, q is a integer from 0 to 4, i is a serial number which, if q is not equal to 0, adopts all integers from 1 to q, where q is as defined above, X_(i) independently of one another, are O, S, NR⁷ or N--(A_(i) --X_(i) --)_(q) --R, A_(i) independently of one another, are unsubstituted or substituted C₁ -C₆ -alkylene, C₂ -C₆ -alkenylene, C₂ -C₆ -alkynylene, C₃ -C₆ -cycloalkylene, C₃ -C₆ -cycloalkenylene, heterocyclylene, arylene or heteroarylene, and R⁷ independently of one another, are H, C₁ -C₄ -alkyl, C₂ -C₄ -alkenyl, C₂ -C₄ -alkynyl, C₃ -C₆ -cycloalkyl, C₃ -C₆ -cycloalkenyl, heterocyclyl, aryl or heteroaryl, and conventional formulation auxiliaries.
 2. The selective herbicidal composition of claim 1, wherein when R⁴ or R⁵ is a radical substituted by C₁ -C₈ -alkoxy wherein 1-3 CH₂ groups which are not bonded directly to one another are replaced by oxygen.
 3. A selective herbicidal composition as claimed in claim 1 wherein in the compounds of formula (I) Ar is an unsubstituted or substituted phenyl or naphthyl radical of the formula ##STR34## in which (u) are identical or different radicals which, independently of one another, are hydrogen, halogen, cyano, nitro, amino or C₁ -C₈ -haloalkyl, C₁ -C₈ -haloalkoxy, C₁ -C₈ -alkyl, C₁ -C₈ -alkoxy, mono-(C₁ -C₄ -alkyl)amino, di-(C₁ -C₄ -alkyl)amino, C₁ -C₈ -alkylthio or C₁ -C₈ -alkylsulfonyl, where each of the 8 last-mentioned radicals is unsubstituted or substituted by one or more identical or different substituents from the group consisting of halogen, C₁ -C₈ -haloalkoxy, nitro, cyano, hydroxyl, C₁ -C₈ -alkoxy, in which one or more CH₂ groups may be replaced by oxygen, C₁ -C₈ -alkylthio, C₁ -C₆ -alkylsulfinyl, C₁ -C₆ -alkylsulfonyl, C₂ -C₈ -alkenylthio, C₂ -C₈ -alkynylthio, C₂ -C₈ -alkynyloxy, C₂ -C₈ -alkynyloxy, C₃ -C₇ -cycloalkyl, C₃ -C₇ -cycloalkoxy, mono- and di-(C₁ -C₄ -alkyl)amino and C₁ -C₈ -alkoxycarbonyl, ando is an integer from 1 to 5 and P is an integer from 1 to 7 or Ar is a monocyclic or bicyclic heteroaryl radical selected from the group consisting of furyl, thienyl, pyrrolyl, pyrazolyl, thiazolyl, oxazolyl, pyridinyl, pyrimidinyl, pyrazinyl, pyridazinyl and quinolinyl, each of which is unsubstituted or substituted by one or more of said radicals U, R is hydrogen, C₁ -C₁₈ -alkyl, C₃ -C₁₂ -cycloalkyl, C₂ -C₈ -alkenyl, C₂ -C₈ -alkynyl, heterocyclyl, phenyl or heteroaryl, where each of the above C-containing radicals independently of one another, is unsubstituted or substituted by one or more radicals selected from the group consisting of halogen, cyano, thio, nitro, hydroxyl, C₁ -C₈ -alkyl, the latter only in the case of cyclic radicals, C₁ -C₈ -haloalkyl, C₁ -C₈ -alkoxy, C₂ -C₈ -alkenyloxy, C₂ -C₈ -alkynyloxy, C₁ -C₈ -haloalkoxy, C₁ -C₈ -alkylthio, C₂ -C₈ -alkenylthio, C₂ -C₈ -alkynylthio, C₃ -C₇ -cycloalkyl, C₃ -C₇ -cycloalkoxy, radicals of the formulae --NR*R**, and --CO--NR*R** and --O--CO--NR*R**, where R* and R** in the three last-mentioned radicals are, independently of one another, hydrogen, C_(`) -C₈ -alkyl, C₂ -C₈ -alkenyl, C₂ -C₈ -alkynyl, benzyl, phenyl or substituted phenyl, or together with the nitrogen atom are a 3- to 8-membered heterocyclic ring which may contain up to 2 further selected heteroatoms from the group consisting of N, O and S, and may be substituted by C₁ -C₄ -alkyl, and (C₁ -C₈ -alkoxy)carbonyl, (C₁ -C₈ -alkoxy)thiocarbonyl, (C₂ -C₈ -alkenyloxy)carbonyl, (C₁ -C₈ -alkylthio)carbonyl, (C₂ -C₈ -alkenylthio)carbonyl, (C₂ -C₈ -alkynylthio)carbonyl, (C₂ -C₈ -alkynyloxy)carbonyl, formyl, (C₁ -C₈ -alkyl)carbonyl, (C₂ -C₈ -alkeny)carbonyl, (C₂ -C₈ -alkynyl)carbonyl, C₁ -C₄ -alkylimino, C₁ -C₄ -alkoxyimino, (C₁ -C₈ -alkyl)carbonylamino, (C₂ -C₈ -alkenyl)carbonylamino, (C₂ -C₈ -alkynyl)-carbonylamino, (C₁ -C₈ -alkoxy)-carbonylamino, (C₂ -C₈ -alkenyloxy)carbonylamino, C₂ -C₈ alkynyloxy)carbonylamino, (C₁ -C₈ -alkyl)aminocarbonylamino, (C₁ -C₆ -alkyl)-carbonyloxy, which is unsubstituted or substituted by halogen, NO₂, C₁ -C₄ -alkoxy or substituted or unsubstituted phenyl, (C₂ -C₆ -alkenyl)carbonyloxy, (C₂ -C₆ -alkynyl)carbonyloxy, (C₁ -C₈ -alkoxy)carbonyloxy, (C₂ -C₈ -alkenyloxy)-carbonyloxy, (C₂ -C₈ -alkynyloxy)carbonyloxy, C₁ -C₈ -alkylsulfonyl, phenyl, phenyl-C₁ -C₆ -alkoxy, phenyl-(C₁ -C₆ -alkoxy) carbonyl, phenoxy, phenoxy-C₁ -C₆ -alkoxy, phenoxy-(C₁ -C₆ -alkoxy)carbonyl, phenoxycarbonyl, phenylcarbonyloxy, phenylcarbonylamino, phenyl-(C₁ -C₆ -alkyl)carbonyloxy, where the 11 last-mentioned radicals are unsubstituted or substituted on the phenyl ring by one or more radicals selected from the group consisting of halogen, C₁ -C₄ -alkyl, C₁ -C₄ -alkoxy, C₁ -C₄ -haloalkyl, C₁ -C₄ -haloalkoxy and nitro, and radicals of the formulae --SiR'₃, --O--SiR'₃, (R')₃ SiC₁ -C₆ -alkoxy, --CO--O--NR'₂, --O--N═CR'₂, --O--NR'₂, --N═CR'₂, --CH(OR')₂, and --O--(CH₂)_(m) --CH(OR')₂, in which the R' in said formulae are, independently of one another, hydrogen, C₁ -C₄ -alkyl or phenyl, which is unsubstituted or monosubstituted or polysubstituted by radicals selected from the group consisting of halogen, C₁ -C₄ -alkyl, C₁ -C₄ -alkoxy, C₁ -C₄ -haloalkyl, C₁ -C₄ -haloalkoxy and nitro, or in pairs are a C₂ -C₆ -alkylene chain and m=0 to 6, or a substituted alkoxy radical of the formula R"O--CHR'"CH(OR")--C₁ -C₆ -alkyl, in which the R", independently of one another, are C₁ -C₄ -alkyl or together are a C₁ -C₆ -alkylene group, and R'" is hydrogen or C₁ -C₄ -alkyl.
 4. A selective herbicidal composition as claimed in claim 3 wherein in the compounds of formula (I)R is hydrogen, C₁ -C₈ -alkyl, C₅ -C₆ -cycloalkyl, C₂ -C₈ -alkenyl or C₂ -C₈ -alkynyl, where each of the 4 last-mentioned radicals, independently of one another, are unsubstituted or substituted by one or more radicals selected from the group consisting of halogen, cyano, nitro, C₁ -C₄ -alkoxy, C₂ -C₄ -alkenyloxy, C₂ -C₄ -alkynyloxy, C₅ -C₆ -cycloalkyl, C₅ -C₆ -cycloalkoxy, mono- and di-(C₁ -C₄ -alkyl)amino, radicals of the formulae --SiR'₃, --N═CR'₂, --O--N═CR'₂, in which the R' in said formulae are, independently of one another, hydrogen, C₁ -C₂ -alkyl or phenyl or in pairs are a C₂ -C₅ -alkylene chain, R^(T) is --CO--R, --NR^(f) R^(g) or --N═CR^(h) R^(i), in which R^(f) and R^(g), independently of one another, are H, C₁ -C₂ -alkyl, benzyl or phenyl or together with the nitrogen atom are pyrrolidin-1-yl, piperidin-1-yl, morpholin-4-yl, piperazin-1-yl or imidazol-1-yl, and R^(h) and R^(i), independently of one another, are H, C₁ -C₂ -alkyl, benzyl or phenyl, R⁴ and R⁵ are identical or different and, independently of one another, are hydrogen, C₁ -C₄ -alkyl, C₂ -C₄ -alkenyl, C₂ -C₄ -alkynyl, C₅ -C₆ -cycloalkyl or C₅ -C₆ -cycloalkenyl, R⁶ is hydrogen, C₁ -C₆ -alkyl, phenyl, benzyl, hydroxyl, NH--CO--NH₂, --NH--aryl or C₁ -C₄ -alkoxy, T is O, S or NR⁷, Q is O or S, q is an integer from 0 to 4, i is a serial number which, if q is not equal to 0, adopts all integers from 1 to q, X_(i) independently of one another, are O, S, NR⁷ or N--(A_(i) --X_(i) --)_(q) --R, A_(i) independently of one another, are unsubstituted, or substituted C₁ -C₄ -alkylene, C₂ -C₄ -alkenylene or C₅ -C₆ -cycloalkylene, R⁷ independently of one another, are H, C₁ -C₄ -alkyl, C₂ -C₄ -alkenyl, C₂ -C₄ -alkynyl or C₅ -C₆ -cycloalkyl.
 5. A selective herbicidal composition as claimed in claim 4 wherein in the compounds of formula (I) R¹ and R², independently of one another, are radicals of the formula ##STR35## or CN.
 6. A selective herbicidal composition as claimed in claim 1 wherein in the compounds of formula (I)X is oxygen and Ar is a monocyclic or bicyclic heteroaryl radical selected from the group consisting of furyl, thienyl, pyrrolyl, pyrazolyl, thiazolyl, oxazolyl, pyridinyl, pyrimidinyl, pyrazinyl, piperazinyl and quinolinyl, each of which is unsubstituted or substituted by one or more identical or different radicals U.
 7. A selective herbicidal composition as claimed in claim 6 wherein in the compounds of formula (I) Ar is 5-chloro-8-quinolinyl.
 8. A selective herbicidal composition as claimed in claim 1, which contains one or more herbicides from the group consisting of carbamates, thiocarbamates, haloacetanilides, substituted phenoxy-, naphthoxy- and phenoxyphenoxycarboxylic acid derivatives and heteroaryloxyphenoxyalkanecarboxylic acid derivatives, such as quinolyloxy-, quinoxalyloxy-, pyridyloxy-, benzoxalyloxy- and benzothiazolyloxyphenoxyalkanecarboxylic esters, cyclohexanedione derivatives, imidazolinones, pyrimidyloxypyridinecarboxylic acid derivatives, pyrimidyloxybenzoic acid derivatives, sulfonylureas and triazolopyrimidinesulfonamide derivatives and S-(N-arylalkylcarbamoylmethyl)dithiophosphoric esters.
 9. A selective herbicidal composition as claimed in claim 8 wherein the herbicide is selected from the group consisting of heteroaryloxyphenoxyalkanecarboxylic acid derivatives.
 10. A selective herbicidal composition as claimed in claim 8 wherein the herbicide is fenoxaprop-ethyl.
 11. A selective herbicidal composition as claimed in claim 6 wherein the herbicide is selected from the group consisting of heteroaryloxyphenoxyalkanecarboxylic acid derivatives.
 12. A selective herbicidal composition as claimed in claim 7 wherein the herbicide is fenoxaprop-ethyl.
 13. A composition as claimed in claim 1, which contains from 0.1 to 99 percent by weight of an active compound of the formula I or a salt thereof or of a mixture of such active compound and a herbicide, and from 1 to 99% by weight of a solid or liquid additive and from 0 to 25% by weight of a surfactant.
 14. A composition as claimed in claim 8, wherein the safener:herbicide weight ratio is from 1:10 to 10:1.
 15. A method of protecting crop plants against the phytotoxic side effects of herbicides, wherein an effective amount of a compound of the formula I as defined in claim 1, is applied to the plants, parts of plants, plant seed or cultivated area before, after or simultaneously with the herbicide.
 16. The method as claimed in claim 15, wherein the crop plants are cereal plants, rice plants or corn plants.
 17. A method as claimed in claim 15, wherein the compound of the formula I or a salt thereof is applied at a rate of from 0.001 to 5 kg/ha of active substance and in a safener:herbicide weight ratio of from 1:10 to 10:1. 